PROCESS SAFETY MANAGEMENT INDIA

Chlorine tonner incident

2012-01-27T10:42:00.000+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this incident:
INCIDENT
In one of the chlorine consuming industry two persons were affected with chlorine while the operator disconnected the tonner from the process due to hard valve operation of the tonner.
DETAILS OF INCIDENT
· The consumer withdraws liquid chlorine from the chlorine tonner and consumes gas after evaporation.
· As per practice, the consumer keeps the tonner in line to withdraw maximum chlorine from the tonner.
· On the specific day of the incident, the operator tried to isolate the tonner at 1.0kg/cm2 pressure when about 40-50 kgs liquid chlorine was left in the tonner and there was ice formation at the bottom of the tonner.
· He could not close the valve fully. The spindle of the valve damaged due to excessive force.
· The operator decided to cut off the tonner by wearing SCBA.
· This action resulted in heavy gas leakage and affected two persons in the surrounding area.
ACTION TAKEN
· The tonner brought to the works.(of the chlorine supplier)
· It was depressurized and the valve was dismantled
· Iron chloride rust and greenish color sludge was observed in the threading of the valve.
· Damaged valve replaced with new valve.
ROOT CAUSE
· Liquid chlorine withdrawal rate is 180 kgs/hr. Maximum liquid chlorine is used up in 4-5 hrs operation at this rate. Some quantity (40-50) kgs remains in the tonner at the bottom.
· Some consumers try to recover this 40-50 kg liquid chlorine as gas by keeping the tonner in line for more time.
· The left over liquid chlorine evaporates at 5-6 kgs/hr as gas and lowers the temperature of the tonner/pipe lines due to fall in pressure till the remaining liquid chlorine is exhausted.
· 1.0 kg/cm2 pressure can lead to about -20 degree C and takes 8-10 hrs to completely empty the tonner.
· Normally chlorine in the tonner is dry. But under such conditions (-200) the same chlorine becomes wet.
· Water in the chlorine separates out and freezes in the spindle of the chlorine valve. It makes the valve hard to operate at that time.
· After attaining normal temperature, chlorine evaporates first and water later. This chlorinated water reacts with the sprindle and makes the chlorine spindle greenish.
· The evaporators which do not have backflow prevention system (from evaporator to chlorine tonner) results carry over of iron chloride rust to valve spindle and makes the valve hard in operation.
LESSONS LEARNT
· The tonners containing some quantity of liquid chlorine (40-50 Kg) are not to be cut off at 1.0kg/cm2. The tonner is to be depressurized by releasing the chlorine to neutralization system through header or evaporator.
· After depressurizing, check that no chlorine gas comes from the upper valve of the tonner, and also check that no ice formation appears on tonner or pipe lines before the tonner is disconnected.
· Chlorine header and evaporator must have chlorine release facility connected to neutralization system.
· Chlorine evaporator must have liquid chlorine flow control interlocked with temperature and outlet pressure to avoid the back flow of chlorine
· Evaporator should have emergency release system with rupture disc and safety valve.
· Temperature of evaporator should be maintained between 80-85 degree C to avoid formation of rust as Fecl3 in the evaporator.
· Dry air (-40 degree) dew point is to be utilized for evaporator maintenance.
· Glass wool filter is to be utilized in gas line to avoid carry over of Fecl3 to main products and choking in chlorine system.
· Tonners can be kept in tilted position forming 20-30 degree angle to withdraw maximum liquid chlorine from the tonner.
MOST IMPORTANT LESSONS
· No chance should be taken with liquid chlorine system. Help of the filler (chlorine supplier) must be taken in such cases. One volume of liquid chlorine expands to 460 times
· Chlorine neutralization system must be effective and checked from time to time.
· Single person should never take this type of emergency job.
· Always stand by person ready with safety equipments should be present during such operations.

Process safety - Seeing and managing

2012-01-24T08:21:00.001+05:30

A typical day for today's plant manager is like this:Punch in....login......read emails and answer......collect data for the meetings scheduled......firefight today's issues.......go back home late in the evening!I was just comparing the daily routine i used to do many years ago in the same position:Punch in....go around the plant for at least one hour.......read the log book.....write relevant instructions in the instruction book.....attend the daily plant meeting for discussing and resolving issues....discuss and take instructions from my boss....communicate these instructions to the plant......go back home peacefully, on time!Note: There were no ISO9000,ISO14000,OHSAS18001,PSM,TQM,Six sigma etc in those days!Managing process safety needs management by seeing, hearing and understanding. Unfortunately today's plant managers do not have the time to see the plant.....this is a dangerous trend. Also competency for managing process safety is lacking. Somewhere we seem to have lost our way!

Awards and Accidents

2012-01-22T15:41:00.002+05:30

Further to the refinery accident during hot work which I had mentioned in my previous blog entry, an article in the Hindu lists out other accidents that occurred in the same refinery in 2009. It also mentions that the refinery won safety awards in 2009 and 2010. There is a disconnect here! Read the article in this link.
While awards are a good way to motivate people, the onus lies on management to sustain and improve process safety performance.Long ago, I had audited an organization that had been granted a prestigious award by an international organization for their safety management system. I visited the plant 6 months after this award. Their safety management was in shambles and I had mentioned to them that the sword is now hanging over your heads.
If everyone goes back home safely everyday and this is maintained, then your process safety management system is working well! Period.

Worker killed in explosion during hot work

2012-01-22T05:57:00.000+05:30

An accident at a SRU at a refinery has killed a worker. Read the article in this link. Please see my earlier posts under safe work practices. Hot work should be done with proper precautions and it is sad that repeated accidents are occuring.

Process Safety and Risk management in the high speed age

2012-01-20T13:09:00.000+05:30

A good article called "Black swans turn grey -The transformation of risk" by Price Waterhouse Coopers highlights the following:

The boards of big organisations do not fully understand the risks that they are running
In the Internet age, speed and prejudice are all
Checks and balances at board level are critical.
Leadership and culture shape an organisation’s attitude to risk.

I think in a chemical industry "operational risk" is of greater importance that financial and strategic risks. As long as there are human beings involved in making decisions, there is a possibility of a process safety incident that has serious implications for the business. That's why I agree totally with the Baker Panel report suggesting that a person competent to understand process safety be on the board of Directors for Chemical Industries.
Read the article by PWC in this link.

Oil rig catches fire

2012-01-19T11:30:00.000+05:30

An oil rig in Nigeria has caught fire and it is reported that two workers were missing and two are hospitalised. Reason for the fire is not known. Read about the fire in this link.

Learning from Buncefield

2012-01-17T09:12:00.000+05:30

The Buncefield incident in 2005 was a wake up call for the industry. A lot of assumptions that were in vogue till then in QRA were overturned. Henry Troth has made a good presentation of the incident mentioning the following:

"Take a critical look at your Safeguards, your Prevention and Mitigation Layers – they may not be as effective as you need
Tanks should have overfill lines from HHH down to ground level to reduce splashing and vaporizing overflowing fuelTank
Overfill Protection should be SIL rated and proven in use
Retrofit water curtains on closely spaced tanks
Fire Pump House should not be a source of ignition (classified area)
Store portable fire fighting equipment and foam in a ‘safe’ place -stationary equipment usually gets knocked out.
Remember – you must keep all Safeguards working as well as the SIS layer(s) – otherwise you are exposed
Is a spill all you need to worry about (what could possibly go wrong)?
Consider consequences carefully – What will you do if the unthinkable happens?"

Download the presentation from this link.

Investigating process incidents

2012-01-15T10:30:00.000+05:30

"Aerodynamically, the bumble bee shouldn't be able to fly, but the bumble bee doesn't know it so it goes on flying anyway" - Mary Kay Ash, American Businesswoman
I like this saying as it is very relevant to process incident investigation. In the course of investigating many process incidents, I have come to the conclusion that you need to be like the bumblebee (keep your mind open, and avoid jumping to conclusion!) while investigating incidents. Many chemical process incidents may apparently not reveal the root causes immediately. I have used the event and causal factor analysis/barrier analysis and Man-Technology-Organization analysis to determine the root causes of many chemical incidents. Also, listen to the people who were present during the incident and observe the incident site. Equipment tell silent tales.

Fire in Guwahati oil refinery

2012-01-11T06:51:00.001+05:30

Read about it in this link.

Three killed in factory explosion in China

2012-01-09T11:30:00.000+05:30

The hazards of thermal expansion

2012-01-07T08:30:00.000+05:30

Many plant personnel do not give importance to thermal expansion safety valves. These are typically small valves and often, the isolation valves are kept closed as they pass. It is human tendency to ignore small things but in process safety it is the small things that cause big disasters!

The CSB had published a good case study on a fatality that occurred due to the bursting of a heat exchanger due to thermal expansion of trapped ammonia. It is worth reading and sharing with all your colleagues. Read it in this link.
The photo at the left is courtesy of the CSB.
Read another incident in this post.
Read a third incident in this post

Cyber security for chemical plants

2012-01-05T14:36:00.000+05:30

Dr Trevor Kletz has said "what you don't have cannot leak". This was with reference to hazardous chemicals. It makes sense then and makes sense now. But with the advent of Internet and remote operation of chemical plants, we often think that the best way to keep a plants intranet secure is not to connect it with the Internet. In other words, "when you are not connected , you cannot be hacked".Last year, the cyber attack on a nuclear development facility in Iran, caused centrifuges to speed up but the control room did not display the increased speed! It is a very interesting story and just imagine what could happen if a cyber take over of critical equipment in a chemical plant takes place? Ensure your systems are adequately protected and conduct cyber security drills along with your regular mock drills! Read the very interesting article about the centrifuge incident in this link.

Process Safety - Keep it simple

2012-01-04T06:55:00.000+05:30

I often think that today we are complicating things too much in process safety, in an already complicated World! This generation of plant operators have been inundated with technology. While some of the technology is excellent, not all of them really help the plant operator. Information overload is the bane of today's PSM programs. When I was a shift in charge at an ammonia plant, we had pneumatic control system (no DCS), but it was so user friendly. I would sit in the center of the control room and at a glance I got to know the plant status. The control room had three operators - one for the front end of the plant, one for the back end and one senior guy looking after both. During emergencies, the senior guy would coordinate the actions very swiftly as he could see the complete plant status just at a glance. The whole ammonia plant had only about 200 alarms that were located on the panel. The critical ones were painted red. By experience we would know which alarm meant what! We never had a serious process safety incident!!I managed to get some pictures to illustrate what I am talking about.

Our control room looked similar to the one at the left. The table at the center was a flat table. The shift engineer used to sit at this table.The control panel is just below the clock.The flowsheet of the entire plant (called a mimic) was depicted at the panel top

This was a field controller. See how simple it is! The red arrow is the setpoint.

This temperature recorder was similar to the one we used to record secondary reformer top temperature and methanator temperature.

The message I am trying to convey is try to keep it as simple as possible. Buy only what you want and not what you get! (This is especially true for DCS and electronic instrumentation)

PSM and PDCA cycle

2012-01-02T08:00:00.000+05:30

The PDCA cycle is the core of any management system. I have seen a common trend from investigating root causes of many chemical plant process incidents - it appears that many of the root causes are due to following the PDCA cycle in a different way: DCA,no P -DO, CHECK, ACT and No PLAN! Fire fighting efforts take place to immediately attack an issue. Productivity, cost cutting and efficiency improvements often take place without undergoing the management of change process. This is why I feel that while certifications to OHSAS 18001, ISO 14001, Responsible Care etc are good, the sustainability of such certifications become questionable. This is evidenced by fatal accidents in companies that are certified. How do we solve this issue? I believe that the onus lies with the top management. If top management are clear about process safety and its implications, then you do not need any system at all! Unfortunately, there is a huge knowledge deficit about the technical aspects of running a chemical plant and the importance of PSM. Recently I had implemented PSM in a pesticide manufacturing unit where the head of the unit was a hardcore experienced chemical engineer. His understanding of the technical nitty gritties of PSM helped me greatly during the implementation. I will end my ranting by repeating two things that Dr Trevor Kletz has said and is highly relevant to Process safety management:1.Walk the talk!2.Keep it simple!

WISH YOU A HAPPY NEW YEAR!

2012-01-01T07:37:00.000+05:30

To all my subscribers and readers,
Wish you and your family a very happy New Year!

Fatality at ammunition factory

2011-12-27T08:01:00.000+05:30

A fatal accident at an ammunition factory has even experts "baffled". The article mentions "Mule, a permanent employee, was described as a highly skilled worker. The incident happened around 2.10 pm when he was about to go for lunch. AFK officials said there was a spark and suddenly Mule was on fire. Showing presence of mind, Mule sprinted towards a water tank and doused the fire. Otherwise, the fire could have spread causing much damage, said some of the employees". Maybe static electricity was the cause??
Read the article in this link
Read another article in this link

The dangers of aerosol cans

2011-12-23T19:51:00.001+05:30

Yesterday I had been to the birthday party of my friend's eight year old daughter. The kids were playing with an aerosol can which generated foam thread, when pressed. None of the kids were aware of the hazards of the aerosol can and that the gas used as a propellant was flammable! What does this have to do with process safety? We also use aerosol cans for dye checking or lubricating/removing rust etc. Read the warnings on the can before you use them. Propane and butane are often used as propellants and the escaping gas can catch fire if a source of ignition is present. Also do not dispose empty aerosol cans in a fire. They can explode.
Thanks to R.Sriram for sending these tips on aerosol cans:

Aerosols contain a product and a propellant that are packed under pressure.
Many people use aerosols without realizing some of the potential hazards associated with them.
Oven cleaners, tile cleaners, pesticides, disinfectants, hair sprays, room deodorizers, paints, and furniture polishes are examples of aerosol products.
When the nozzle of an aerosol is pressed, the product and propellant are released from the container in a fine mist.The actual product propelled by the aerosol, such as some oven cleaners, can be corrosive, flammable, or poisonous.Acute symptoms of aerosol exposure include headache, nausea, dizziness, shortness of breath, throat irritation, and skin rash.
A misdirected spray can cause eye injury and chemical burns.
Never leave or place an aerosol can near high heat sources, such as a heater, direct sunlight, or fire.
Keep aerosol cans away from children and pets.
Never puncture or subject an aerosol can to sharp impact; a sudden puncture may cause an explosion.
Dispose the Aerosols in a proper way.

A water tank kills

2011-12-21T07:30:00.001+05:30

A supervisor was killed when he attempted to rescue his fellow worker who had collapsed after entering an empty water tank. Investigation is on to determine what was present inside the water tank. If a water tank can kill, just imagine the hazards you face when you enter a confined space in a chemical factory. Follow your company procedures strictly and don't take any confined space for granted. Read the article about the water tank fatality in this link.

Two killed in pharma factory fire near Hyderabad

2011-12-20T13:00:00.000+05:30

A news article mentions that a fire in a pharma factory at Patancheru has killed two people. The article mentions that
"According to police, the fire engulfed the factory after a reactor exploded due to an electrical short-circuit. The fire broke out in the evening, and spread to neighboring factories. Fire-fighting personnel had to battle for five hours to control the flames.This is the second such accident in three days. Four workers of a chemical factory were killed in a reactor blast at Polepalli Special Economic Zone (SEZ) at Jadcherla in Mahabubnagar district near Hyderabad last Friday".
Read the article in this link
See a photo in this link.

The dangers of sewers

2011-12-19T08:03:00.002+05:30

Two people were reportedly killed in a factory in Chennai when they entered a sewage tank that was not opened for a long time. Be careful of sewers in your factory and residential colonies. Entry should be done only with proper confined space entry permits

The dangers of water hammer

2011-12-19T07:54:00.005+05:30

Many of you would have heard the "banging" noise that a water hammer produces inside a pipeline. We also do not expect a pipeline to be destroyed by water hammer. But it happens. An article by Gregg Basnight mentions the following:
"Contrary to old operating practices to drain and warm up steam lines, "Cracking Open" valves in lines to bleed condensate under steam pressure is NOT safe and has resulted in numerous reported water hammer fatalities.Before admitting steam to any line, the condensate must be removed. Condensate should be assumed to be in all low points and dead legs until proven otherwise by verification of drain or steam trap position and operation. Pressurized dead legs without functioning traps or periodic manual blowdowns will have condensate present. The affected section of piping should be isolated, depressurized and drained before restoring steam to the system".
Read the full article in this link.

Give importance to sight glasses

2011-12-17T07:27:00.000+05:30

30 years ago, in the ammonia plant where I worked, the sight glass of a high pressure (200 Kg/cm2) ammonia separator leaked during start up. Luckily we managed to shut the plant down safely with no injury to anyone. The root cause was the wrong torquing procedure used. A good article about sight glasses mentions the following:

"Proper design, installation and maintenance of sight glasses are the keys to their safe and effective use....a sight glass almost always fails in tension rather than compression. This is similar to the case for concrete, because glass is not ductile and cannot stretch like metal. Therefore, tiny imperfections in a sight glass window can create stress concentrations, which are potential failure points. Just the touch of a finger on the window can reduce the tensile strength of a virgin glass element by three orders of magnitude from one million to 1000psi. Although design and manufacturing flaws are important, most sight glasses fail due to improper installation. Mechanical stress is a frequent cause, arising from the over-tightening or uneven torquing of bolts that generate bending loads on the glass. When an existing sight glass window is replaced, trapped debris may become a problem if old gaskets have baked onto the flanges. While this may seem trivial, it is actually very dangerous. Even small contaminant particles or build-up might be enough to scratch, pit or bend the new glass during installation".

Laser scanning - a tool for Management of change and Asset Integrity

2011-12-14T08:00:00.000+05:30

The most difficult elements to implement in a PSM program are management of change and asset integrity simply because of the large quantity of data involved and less time available. I was reading an interesting concept of laser scanning in an article in Power magazine. It mentions the following:
"Laser scanning also provides a dimensionally accurate representation of the plant and all its equipment as well as a photographic quality visual representation. The laser scan database can be integrated with a variety of plant design applications to provide comprehensive facility management support".
The concept will be very useful for PHA teams who are analysing changes/modifications as they can virtually "see" the proposed modification. It is also an useful tool for managing your asset integrity as another article mentions.
Read the article on laser scanning in this link
Read the article on Virtual asset integrity management in this link.

US Unions briefing on Process Safety

2011-12-11T12:04:00.000+05:30

The USW union of the US has briefed the US Congress about health and safety problems in the oil industry. As per a news article,"USW Health and Safety Specialist Kim Nibarger outlined five fatal flaws at the briefing on where the oil industry needs to improve its health and safety record: process safety, mechanical integrity, management of change, incident investigation and control room alarms and instrumentation. “When things go bad in a refinery, they go really bad and people die,” he told the briefing. “Focusing on personal safety—the wearing of hard hats and safety glasses, slips, trips and falls—says nothing about how safe a refinery is for workers and the surrounding community. BP had a low personal injury rate at its refineries, but the 2005 explosion and fire at its Texas City plant showed it failed miserably in terms of process safety. Fifteen people were killed and 170 were injured in the 2005 accident as a result of this failure. “The oil companies are playing Russian roulette with their equipment,” Nibarger said. “They are doing quick, stopgap fixes, like placing clamps on pipes instead of replacing the pipe. They’re extending the time between unit shutdowns when all the equipment is checked. When there is a shutdown they’re not always repairing or replacing critical equipment. When they do repair equipment they’re not bringing it up to current RAGAGEP (Recognized and Generally Accepted Good Engineering Practices) standards.”
If the above sound familiar to you, take a hard look at your PSM program!
Read the full article in this link.

Adding too much chemical causes an incident

2011-12-09T15:27:00.000+05:30

A news report mentions an incident where an orange gas cloud leaked from a manufacturing facility for making ferric sulphate. Apparently, too much nitric acid was added to a batch, resulting in a violent reaction that produced excess amounts of nitrogen dioxide that escaped from the reactor into the air.Nitrogen dioxide is a reddish brown gas and is highly toxic if inhaled and is also corrosive.
Ensure that you have proper controls over addition of chemicals, especially if adding an excess of one chemical can trigger something unwanted. Engineering controls are the best to avoid such mishaps. Depending only on an SOP in such situations may cause an an incident to happen.
Read the article in this link.

Boiler burst kills 4

2011-12-07T07:44:00.001+05:30

A boiler of a dyeing unit burst on Tuesday, killing four persons and injuring 20 others on Tuesday. Inquiries are on to find out the reason for the blast. An official said that the safety valve failed release in time, leading to pressure building up inside the boiler.Read about it in this link.

A change in piping material may overlook something else!

2011-12-06T11:19:00.000+05:30

A plant decided to change its sulphuric acid piping from Cast Iron to SS. However, they decided to conduct piping design analysis as per code requirement.The analysis found out that design did not adequately consider the difference in cross-sectional thickness between Cast Iron and SS (Cast iron is very thick compared to stainless steel). Also, the heat transfer rates of CI and SS differ. The piping expert redesigned the piping system to account for the thinner cross-section and thermal expansion properties of stainless steel and thus avoided premature failure.
Read the article in this link.

Explosion in sulphuric acid tank

2011-12-04T08:27:00.000+05:30

An explosion in a sulphuric acid tank has injured four personnel in Japan. There is the danger of presence of hydrogen in sulphuric acid tanks and when you do hot work be aware of the simple precautions like gas testing etc.
Read about the accident in this link. The Chemical Safety Board had earlier brought out a safety bulletin on the Dangers of Hot work, which is worth reading for every plant operation, maintenance and safety personnel. Read it in this link.

Fire in Pharma Plant

2011-12-02T09:50:00.000+05:30

A fire in the vacuum dryer area of a pharma plant has reportedly seriously injured three people. As per Company press release, it states "There was a fire incident in a powder processing area at early hours on Nov 28,2011, at unit 11 which is located at Pydibhimavaram, Srikakulam near Vizag, A.P. Three persons were injured and they were taken to the hospital. The powder processing area is isolated from the intermediate block. There was no impact to the operations as well as to the assets".
Another news report indicates that the fire was caused by an explosion due to high pressure in the vacuum dryer.
Read the news reports in these links
Link 1
Link 2
Link 3

Remembering Bhopal............

2011-12-01T07:00:00.000+05:30

Please spend December 2nd/3rd as “Process Safety Day” in your organisation. Educate your personnel on the Bhopal Gas tragedy and its lessons. 27 years ago, on the night on December 2nd/3rd, 1984, on a wintry night in Bhopal, thousands of men, women and children died an excruciating death when MIC leaked from the Union Carbide factory. The survivors and the next generation children born to those exposed to the gas still are suffering from the effects of the gas. Bhopal is an ongoing tragedy and should never be forgotten. The Bhopal gas disaster comprises actually of three disasters - the first was the actual incident, the second was the inadequate compensation received and the third is the ongoing legacy of genetic defects and effects of the hazardous waste that has seeped into the ground water. Every plant operating, maintenance and safety personnel must never forget the lessons of Bhopal. They are still relevant today:
1. Do not cut costs without looking at the effects on process safety
2. Maintain all your layers of defense including asset integrity
3. Continually ensure that competency of personnel operating and maintaining plants are updated and current
4. Be prepared for the worst case scenario.
5. Understand the risks and measures to eliminate / reduce or control them
6. Learn from your past incidents. Those who do not learn are condemned to repeat the incidents.
7. Pay heed to your process safety management system audit reports

As you are aware, this blog is also dedicated to the surviving victims of Bhopal and for my regular subscribers, I appeal to you to buy my book "Practical Process Safety Management", the proceeds from which are donated to the surviving victims of Bhopal.Contact me at bkprism@gmail.com for buying the book.

See a presentation on the Bhopal Gas Tragedy by Vijita S Aggarwal, Associate Professor, University School of Management Studies,GGS Indraprastha University,Delhi, India in this link.
Read my older post comparing the Bhopal and the BP incident of 2005 in this link
Read the then Police Chief’s account of the tragedy in this link.

Witness to a catastrophic near miss!

2011-11-29T08:58:00.000+05:30

On 29.11.1984, I was working as Shift in Charge in an ammonia plant when a cylcone hit the place. Management had taken advance action and instructed us to shut off the back end of ammonia plant (the back end of the ammonia plant involves high pressures). We had shut down the back end and were waiting for the cyclone to hit us. The wind speeds were very high and all of us were taking shelter in the control room. A complaint then came in from the another plant that was located within the same complex, that they were experiencing severe ammonia odour. Thinking that the pilot burners of the ammonia derrick supported flare that was provided for emergency venting of the ammonia storage tank was put off by the high winds, I requested operators to go out and check them. Three operators had to go, holding each other tightly,as the wind speed was so high and could blow a man off his feet. After a short while they came back and reported that the flare was missing. I went out to check with another team and we found to our horror that the flare structure had collapsed on the main ammonia vapor line coming from the tank. The derrick structure was weak and could not bear the brunt of the wind speeds, but the main flare gas pipe was in good condition and when the derrick toppled, the main gas pipe prevented it from falling all of a sudden. Instead it fell slowly and came to rest on the ammonia vapor line! The 8" main ammonia vapour line from the tank was dented, but did not leak.
When you conduct your asset integrity program, pay attention to structures. Nowadays, in many plants, painting schedules are taking a back seat, with the net result that corrosion creeps in. Corrosion is a silent killer. It will hit you one day if you don't maintain your assets.
Interestingly, recently I read an article where a complete flare structure repair was done with minimum downtime in a plant.Read the article in this link.

Escaping from steam

2011-11-25T18:24:00.001+05:30

Many of you will be working with steam. During startups the possibility of water hammer in a steam pipeline has the potential to rupture the line or flange joints. Your SOPs must warn operators about the dangers of water hammer. An article mentions that the best way to escape from a closed space in which a steam leak has been triggered due to water hammer is to escape in the direction in which the steam is leaking through an exit. Read this article in this link

Heat transfer fluids

2011-11-22T08:12:00.000+05:30

Paratherm have brought out a good booklet on heat transfer fluids - do's. dont's and best practices. Some of the points brought out are:
"If any hydrocarbon liquid (oil, grease, heat transfer fluid, hydraulic fluid) is allowed to enter porous insulation, it will begin to oxidize, raising the insulation’s internal temperature. If this temperature exceeds the fluid’s autoignition temperature, the fluid is likely to spontaneously combust into a smoldering fire. Thoroughly inspect all insulation for signs of wetness and other damage.Although “hydro” testing is a commonly accepted practice with heat transfer systems,alternatives such as pressure-testing with inert gas or with the heat transfer fluid itself should be considered. Water in a system can cause pump cavitation and corrosion and, if trapped in a “dead leg” and hit by high-temperature oil, can flash to steam and literally blow the pipe or tubing apart. And if the pipe doesn’t burst, the expansion can push a slug of hot oil out the expansion tank’s vent—a serious safety hazard".
Read the complete article in this link.

Blast in melamine plant kills 14

2011-11-20T18:20:00.001+05:30

A BBC news report indicates that 14 people were killed in a blast in a melamine plant in China when work was going on an heat exchanger. Read the news report in this link. The cause of the explosion is not known.
The European agency for safety and health and work reports an incident in 2003, in Netherlands, where three maintenance workers were killed when a gas oven in a melamine plant exploded and the three workers who were standing on the cover of the oven fell into it.The gas oven was fired by natural gas and off gases from neighbouring plants. The off gases were contaminated and were filtered before use. The filters had to be cleaned regularly. A short cut taken during maintenance of these filters created a combustible mixture of gas and air in the oven which was ignited by a stray spark. Although this was the immediate cause of the explosion, investigations concluded that the underlying cause was a company culture which had allowed the untested short cut procedure to be used.
The lesson is to follow safe procedures and not to take short cuts even under time pressure. The accident also highlights the importance of the safety culture. Read the report in this link.

Chlorine leak in paper mill

2011-11-20T11:33:00.000+05:30

Thanks to Abhay Gujjar for sending information about a chlorine leak from a chlorine dioxide storage tank in a paper mill. Four people are reported taken to hospital.
TAPPI, the leading association for the worldwide pulp, paper, packaging and converting industries has published a booklet on safe handling and storage of Chlorine dioxide. The following points are mentioned:
Chlorine dioxide gas is unstable and readily decomposes to chlorine and oxygen under upset conditions
Chlorine dioxide decomposition is a propagating reaction similar to a combustion front or flame. Providing a sweep of fresh air across the vapor space of a storage tank has shown to reduce the probability and violence of decomposition.
Read the complete guidelines in this link.
Read about the incident in this link.

Bio Fuels and Process Safety - Ethanol Tanks

2011-11-19T08:04:00.001+05:30

The bio fuel industry is growing at a rapid pace. However, from a process safety point of view, it is hazardous as it deals with flammable chemicals like ethanol. An article mentions the following:
"Steel tanks containing fuel-grade ethanol develop leaks due to stress corrosion cracking, says Oliver Moghissi, president of the National Association of Corrosion Engineers. Corrosion can be an issue near vents and any external appurtenances exposed to air, allowing ethanol to pick up moisture. Storing hydrous ethanol can produce even more corrosion due to higher water content.
There are a number of corrosion mitigation strategies, he adds, drawing on technical input from Narasi Sridhar, vice president of DNV USA, a classification society, and a fellow member of NACE. Galvanic sacrificial coatings, such as zinc or aluminum, will protect steel tanks containing ethanol. The main limitation to this system of corrosion mitigation is that it could have a negative effect on product quality. “Any dissolved metal species in the ethanol can render the ethanol unacceptable to the automotive industry, its main customer,” he tells EPM. “Any galvanic coating therefore must be tested rigorously by the end-user, the automotive community, which can be time consuming and expensive.”
Cathodic protection, however, doesn’t work for the insides of metal structures containing ethanol, the corrosion engineers add. The fuel has low electrical conductivity when compared to water and, as a result, much of the applied voltage is insulated from the metal needing to be protected. “Therefore, impressed or sacrificial cathodic protection systems will not work in ethanol,” Moghissi says. “In ethanol-gasoline mixtures, the situation is even worse since gasoline has a lower electrical conductivity than ethanol.”Read the full article in this link.

Vacuum - a deadly killer

2011-11-15T19:23:00.001+05:30

A news article mentions that a man was sucked into a huge duct conducting gaseous silicic acid that led to his death. The duct was about three feet in diameter. Besides inhaling the gas, he had also suffered injuries on the head while being sucked in. Another employee was also partially sucked into the duct but managed to escape with minor injuries.Read the article in this link.

Dust explosions - status of regulations in USA

2011-11-14T17:52:00.001+05:30

An AP news article mentions the lack of regulations in the USA regarding dust explosions.
"Figures compiled by the U.S. Chemical Safety Board illustrate the scope of the problem. A 2006 study reported there were at least 281 dust explosions in the U.S. between 1980 and 2005 that killed 119 workers and injured 718. In 2007, it recommended that the Occupational Health and Safety Administration create workplace rules to control dust and cut down on explosions. The Chemical Safety Board is charged with investigating industrial accidents, but it must rely on regulatory agencies like OSHA to effect change from its findings.
"Despite the seriousness of the combustible dust problem in industry, OSHA lacks a comprehensive standard to require employers in general industry to implement the dust explosion prevention and mitigation measures," the Chemical Safety Board wrote in its 2007 report".
Read the full news article in this link.

Ammonia tank safety valve release

2011-11-12T07:52:00.001+05:30

An ammonia tank in a plant in Australia apparently released close to 1 MT of ammonia through its safety valves due to overpressure of the tank. The plant has been ordered to close down.The Government spokesperson correctly mentions that a safety valve is the last line of defence and this is a serious incident. Many atmospheric ammonia tanks and LPG bullets have their safety valves open to atmosphere. With rampant unauthorized residential settlements still happening around chemical industries and refineries in India, is a disaster waiting to happen?
See the video and report of the incident in this link.
Read a press release of the incident by the company in this link.

More chlorine incidents

2011-11-11T11:40:00.000+05:30

Thanks to Mr Harbhajan Singh Seghal for sharing these incidents.

INCIDENT #1
Chlorine leakage was noticed from the valve of a chlorine tonner. They tried to control the leakage but when it became uncontrollable, they dumped the leaky tonner into the alkaline sump to neutralize the remaining chlorine. According to media, about thirty persons complained of eye irritation.
ROOT CAUSE

4 Nos filled chlorine tonners were stored since Dec 2008 in the open area. Out of which one toner has leaked
Valve caps & protection domes were also not provided on these tonners.
Minor chlorine leakage from the valve of chlorine tonner remained unattended which resulted into a major leak
Chlorine is a dry gas .On leakage it attracts moisture from the atmosphere and increase the corrosion rate at a very high rate
Storage in the open makes the accessories weak and further adds up to corrosion

LESSONS LEARNT

Tonners should be stored under proper shed to protect them from direct sun light & heat.
Valve caps & protection domes must be provided on the valves of tonners, if they are not being used.
Regularly chlorine tonners area to be inspected for any chlorine leakage with the help of ammonia torch.
Even if minor chlorine leakage is noticed, the same must be attended immediately and should not be left unattended.
Filled Tonners should not be stored for more than 90 days.
Sufficient nos of necessary PPE’s & tonner emergency handling kit should be readily available at user end.
Periodic refresher training should be organized for employees handling chlorine tonner.
Emergency handling procedure should be available at consumer end.

MOST IMPORTANT
Under no circumstance, leaky chlorine tonners should be dumped in alkaline water sump which may cause major mishap.
Tonner keeps floating on the surface of water and chlorine does not neutralize in the solution but spreads in the atmosphere
Chlorine attracts moisture from water and further adds to corrosion
Filler should be informed on first sight of leakage
Even the leaked tonner though empty should be made safe by washing and drying and destroy as per rules

INCIDENT #2
The Incident of bulging of filled chlorine toner occurred but there was no chlorine leakage.
INCIDENT CONTROL
The bulged tonner was immediately depressurized partly by releasing the chlorine to a 200 litre barrel having 5% dilute Caustic lye solution to reduce the pressure & temperature of the tonner and avoid its bursting. Thereafter the tonner was emptied by using the balance chlorine in their process. The emergency could be handled safely & successfully by the chlorine user.
ROOT CAUSE ANALYSIS

Quantity of liquid chlorine was higher than the desired quantity and moreover the filled tonner was kept in the sun
The temperature and pressure of the tonner increased due to this.
The tonner got bulged due to high thermal expansion of liquid chlorine with temperature.

LESSONS LEARNT

Filling of chlorine toner should be done as per filling ratio-1.19. Water capacityx1.19
Weight of tonner should be rechechecked after filling
Filled tonners must be stored in cool and well ventilated place
Tonner can bulge at 45 degree centigrade with 5%excess filling.it can bulge at any time at room temperature with 10% excess filling

Electrical Safety - part of process safety

2011-11-08T09:08:00.005+05:30

Mr Vijayraghavan shared news about an incident in Germany on 4th November when a worker died in an accident during repair work at a petrochemicals hub. The worker died as a result of an electrical shock suffered during repair work on a crane. Investigation is on to determine the cause
Schneider Electric has brought out a very good free safety video on electrical hazards . They mention that “Arc flash accidents that cause serious and sometimes fatal injuries occur five to 10 times every day in the United States. Schneider Electric has produced this electrical safety video as an awareness tool for anyone who faces a risk from electrical accidents that might occur when work is performed on energized electrical equipment. Safety standards are now in place to address the safety of workers who may be exposed to these hazards, as well as to inform employers of their responsibilities to provide employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees. This video provides information about arc flash, arc blast, shock, and electrocution hazards”.
See the low resolution video in this link
Download the high resolution video from this link and share it with all your colleagues,technicians and operators. It may prevent a fatality.

Domino effects in a disaster

2011-11-07T11:30:00.000+05:30

A good example of domino effects of a blast occurred in July 2011 in Cyprus when munitions in a military dump located near to a power generation station blew up. The blast damaged the power station leading to severe power shortages in Cyprus. An article mentions the following:
'Twelve people have been killed and about 30 injured in a blast at a munitions dump in Cyprus. The island's largest power station has been damaged, resulting in widespread power cuts.
The force of the dawn explosions blew out virtually every window in the neighboring village of Zygi and extensively damaged the islands main power station, which remains offline.
Large-scale damage could be seen to a huge section of the barriers of the main Larnaca-Limassol highway and a huge crater about 500 meters from the power station was shown on state TV."
Read the article in this link
See pictures of the blast damage in this link.

Chlorine leak incident

2011-11-05T06:35:00.000+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this incident report:

INCIDENT OF CHLORINE LEAKAGE
Two persons were gassed in one of the chlorine consuming industry near Baroda. When the operator disconnected the tonner on the pretext of the hard valve operation of the tonner.
DETAILS OF INCIDENT

The consumer withdraws liquid chlorine and consumes gas after evaporation.
As per practice the consumer keeps the tonner in line to withdraw maximum chlorine from the tonner.
On the specific date the operator tried to isolate the tonner at 1.0kg/cm2 pressure when about 40-50 kgs liquid chlorine was there in the tonner and ice formation was there at the bottom of the tonner.
He could not close the valve fully. The spindle of the valve damaged due to excessive force.
The operator decided to cut off the tonner by wearing SCBA.
This action resulted in heavy gas and affected two persons in the surrounding

ROOT CAUSE OF THE PROBLEM

Liquid chlorine withdrawal rate is 180 kgs/hr. Maximum liquid chlorine is used up in 4-5 hrs operation at this rate. Some quantity 40-50 kgs remains in the tonner at the bottom. Some consumers try to recover this as gas by keeping the tonner in line for more time This Liquid chlorine evaporates at 5-6 kgs/hr as gas and lowers the temperature of the tonner/pipe lines due to fall in pressure till the exhaust of liquid chlorine. 1.0 kg/cm2 pressure can lead to about -20 degree C and takes 8-10 hrs to become completely empty.
Normally chlorine in the tonner is dry. But under such conditions (-20 degree) the same chlorine become wet. Water in the chlorine separates out and freezes in the sprindle of the chlorine valve. It makes the valve hard to operate at that time.
After achievement of normal temperature chlorine evaporates first and water later. This chlorinated water reacts with the spindle and makes the chlorine spindle greenish.
The evaporators which do not have backflow prevention system (from evaporator to chlorine tonner) results carry over of iron chloride rust to valve spindle and makes the valve hard in operation.

ACTION TAKEN

The tonner brought to the works.
It was depressurized and valve dismantled.
Iron chloride rust and greenish color sludge observed in the threading of the valve.
Damaged valve replaced with new valve.

SUGGESTED ACTION

The tonners containing some quantity of liquid chlorine are not to be cut off at 1.0kg/cm2 till Chlorine pressure is released to neutralization system through header or evaporator.
No Cl2 gas from the upper valve of the tonner
No ice formation appears on tonner or pipe lines after depressurization.
Chlorine header and evaporator must have chlorine release facility connected to neutralization system.
Chlorine evaporator must have liquid chlorine flow control interlocked with temperature and outlet pressure to avoid the back flow of chlorine.
Evaporator should have emergency release system with rupture disc and safety valve.
Temperature of evaporator should be maintained between 80-85 degree C to avoid formation of rust as FeCl3 in the evaporator.
Dry air (-40 degree) dew point is to be utilized for evaporation maintenance.
Glass wool filter is to be utilized in gas line to avoid carry over of Fecl3 to main products and choking in chlorine system.
Tonners can be kept in tilted position forming 20-30 degree angle to withdraw maximum liquid chlorine from the tonner.

CONCLUSION

No chance should be taken with liquid chlorine system. Help of the filler must be taken in such cases. One volume of liquid chlorine expands to 460 times
Chlorine neutralization system must be effective and checked from time to time.
Single person should not take this type of emergency job.
Always there should be two persons with safety equipment.

Taking mock drills seriously

2011-11-03T08:05:00.000+05:30

Mock drills, if well planned, do deliver inputs where areas for improvements are needed. It is very important to follow up on the results of mock drills and act on them. An off site mock drill conducted in the US demonstrates the seriousness of the effort. In an article about the drill, it mentions that
"The drill, which began just before 9 a.m. Wednesday with the sounding of emergency sirens throughout the county, serves to ensure all emergency agencies in the county are ready in the event of a chemical emergency at the Blue Grass Army Depot, said Justine Barati, congressional liaison with the Joint Munitions Command who also works with CSEPP.A group of 28 evaluators from across the country watched the drill in Madison County, and will report on the strengths and weaknesses of the various agencies’ response, Barati said.Wednesday’s “accident” happened when two people working in the chemical area at the depot fell into some of the chemical. A third person then suffered a heart attack, Barati said. The spill involved an M55 rocket that contained GB nerve agent."
Read the report on the drill in this link.
View a video on another Homeland Security Drill where 300 zombies participated, in this link.

The importance of sight glasses in process safety

2011-11-01T07:56:00.002+05:30

IIChE special issue on Process Safety

2011-10-30T15:14:00.005+05:30

The Indian Institute of Chemical Engineers is bringing out a special issue on Process Safety and risk management to coincide with the anniversary of Bhopal disaster in December. You can view the call for papers in this link.

Safe distances during a BLEVE

2011-10-26T11:07:00.002+05:30

Firefighters have to maintain a safe distance when responding to a possible Boiling Liquid Expanding Vapour Explosion. A video in you tube demonstrates that for a 400 L bullet, the minimum observations distance is at least 90 M. But at this distance, they may still be hit by projectiles. See the video in this link. Worth watching for all emergency response teams. Another information in the video is that for a 400 L bullet, you will need 200 lpm of water to keep it cool, for a 4000 L bullet you will need 700 lpm and for a tanker you will need 2000 lpm of water...

When things go wrong – Parkinsons law in emergencies

2011-10-25T12:46:00.000+05:30

A hydrocarbon spill occurred in a plant and caught fire. Sulphuric acid pipelines nearby leaked and were dumping suplhuric acid into the hydrocarbon spill. The sulphuric acid was breaking down the fire fighting foam used by firefighters and delayed the extinguishing of the fire.
In my experience of handling many emergencies, things will go wrong during an emergency. The better prepared you are, the better you are equipped to handle surprises.

Chlorine incidents

2011-10-24T11:29:00.000+05:30

An article in the Scientific American highlights the following:
"Over the past 10 years, chlorine has been involved in hundreds of accidents nationwide, injuring thousands of workers and townspeople, and killing some, according to federal databases. It is second only to carbon monoxide when it comes to the percentage of accidents that cause injuries, according to the newest federal data.
Chlorine is one of the most widely used industrial chemicals in the world today, with 13 million tons produced annually in the United States alone.
In 2009 alone, chlorine was involved in 181 reported accidents with 56 resulting in injuries, based on the latest report from a federal database called Hazardous Substances Emergency Events Surveillance (HSEES). That amounts to 3.8 percent of all the reported chemical emergencies that year. Chlorine had a high percentage with victims, 30.9 percent, second only to carbon monoxide, which had 41.7 percent with victims. Roughly one-third of the states reported, and only for a part of the year, so the real number of accidents and injuries is much higher, experts say
Incidents are rare" in the production of chlorine among Chlorine Institute members, said Frank Reiner, president of the national trade group of 220 manufacturers and distributors. In an e-mail, Reiner said, "the safety performance of the industry has been very good" and his group shares information among members to avoid future problems".Read the article in this link

H2S leak in lubricant plant

2011-10-23T10:42:00.000+05:30

A H2S leak has been reported at a lubricant plant in USA. It is reported that a small amount of the gas was released when an additive for oil-based vehicle engine lubricants overheated. Other news reports indicate that a tanker truck overheated and released H2S. I just randomly looked up a MSDS of an automotive lubricant and it does warn about heat as one of the conditions to avoid and also identifies H2S under exposure controls/personal protection.
Read the article in this link. Read another report in this link
Read the MSDS of a automotive lubricant in this link
Read a technical bulletin of an overview of H2S including its hazards in this link.

Explosion protection and instrinsic safety

2011-10-22T11:20:00.000+05:30

Pepperl + Fuchs have brought out a simple and effective presentation of explosion protection and intrinsic safety. Their presentation summarizes the following:

"A hazardous location is an area in which the atmosphere is explosive or anticipated to be explosive
Intrinsic safety dates back to 1913 following a disastrous mine explosion in England
The Ignition Triangle consists of three components (fuel, ignition energy and oxidizer) that must be present simultaneously, and in suitable proportions, to cause an explosion.
Minimum Ignition Energy (MIE) is the ideal ratio of fuel to air where the mixture is most easily ignited
Any area above or below the Minimum Ignition Energy contains a smaller fraction of air or combustible gas/fuel and cannot be ignited
Hazardous areas in North America are broken down into three classifications: Class I (flammable gases or liquids), Class II (dust), and Class III (fibers and flyings)
The classifications are further broken down in Division 1 or Division 2 based on the probability of the materials being present in a potentially hazardous quantity
The Division Method of North America is comparable to the Three-Zone Model practiced in Europe
There are three basic methods of explosion protection: containment, segregation, and prevention
Intrinsic safety is the principle of keeping the electrical energy below the MIE and is the preferred method of explosion protection for low power devices"

Download the complete presentation from this link

Adding chemicals -fast or slow??

2011-10-19T10:53:00.000+05:30

An incident occurred in UK in 2007 when an operator was adding a solid chemical to a reactor containing a liquid chemical. When they initially failed to react, he added more of the solid chemical Suddenly an uncontrolled runaway reaction occurred. A report by UK Health and Safety executive mentions the following:
"None of the workers were in the production hall when the alarms - set off by the incident - began to ring, but one of them returned to investigate. He was driven back by the fumes and fled from the building.
The HSE investigation concluded the company had failed to adequately assess the risks of the chemical reaction and ensure that suitable control measures were in place. It also found the employee had not received adequate training, instruction and supervision on the operating procedures, and did not appreciate the danger of increasing the quantity of the chemical".
Read the full report in this link.

Process Safety - Ensure you use correct materials of construction

2011-10-16T19:28:00.000+05:30

An Australian company has been fined for a sulphuric acid valve failure that led to the amputation of a worker's leg.It appears that when employees went to check the cause of of an acid line choke, a valve failed and sprayed them with concentrated sulphuric acid.Investigation determined that the valve that failed was not of correct material of construction and was designed to carry 40% sulphuric acid. This resulted in the failure of the valve. Often material changes go unnoticed till a catastrophe happens. Ensure your management of change process and your inspection procedures are stringent.

Blackberry and Process Safety

2011-10-14T06:02:00.003+05:30

The recent disruption is services for people using the Blackberry phone was attributed to the failure of a core switch and failure of its back up. There are lessons in process safety from the blackberry incident! Are your back up systems working properly? Do you check the reliability of your back up devices? Remember, many incidents have occurred because the back up failed when it was needed....
Read the article about the Blackberry failure in this link.

Process Safety - Have you considered Tank Tsunami's?

2011-10-12T19:36:00.000+05:30

On April 7th this year, a 30,000 gallon water tank in the US state of Florida failed creating a Tsunami like wave that caused a building to collapse, killing two workers. Read about it in this link.
With storage tanks for petroleum and other chemicals becoming larger and larger, you must have a strong integrity management program to ensure these tanks do not collapse and create a man made Tsunami, with accompanying catastrophic consequences.

Safety features at Kudankulam Nuclear Plant

2011-10-10T09:00:00.003+05:30

The Kudankulam nuclear plant has been in the news recently due to the protests by the locals. An article in the Business Standard by the former Chairman and current member of the Atomic energy commission mentions the following additional safety features provided:
"The nuclear power units in Kudankulam belong to the third generation of design evolution; the Fukushima reactors belong to the first generation design. A special feature of the Kudankulam design is the passive cooling system for the nuclear reactor core. The water cooling the reactor transfers its heat to the water in the steam generators. After driving the turbine, steam condenses into water in the condenser and is pumped back to the steam generator. In an abnormal situation, when no power is available to drive these pumps, the hot water in the steam generator flows to an air-cooled heat exchanger located at a height outside the reactor building. Owing to the difference in height, the hot water rises up on its own due to its lower density and cold water flows down to the steam generator. This is called the “thermo siphon effect” and it does not need any pump to move the water. This feature was incorporated in the Kudankulam design at India’s insistence. The Kudankulam reactors are the first to have the passive cooling feature. The Kudankulam design has another important feature” a “core catcher”. In the event of an extreme accident and were the molten nuclear fuel to breach the reactor pressure vessel, it falls on to a matrix containing a large amount of neutron-absorbing substances (such as boron). Once mixed with this material, the nuclear fuel is rendered incapable of starting a nuclear chain reaction. Only the latest design of nuclear power units have this safety back-up system".
Read the complete article in this link.

R & D and Pilot Plant Vs Process Safety

2011-10-08T13:18:00.000+05:30

I visit a number of pilot plants that are run by the R & D department of companies. I see a common trend that affects process safety. In many plants, the R &D and pilot plant is being run by competent doctorates in Chemistry. However, designing and operating a pilot plant requires knowledge of chemical engineering principles. The common gap I observe is the lack of application of chemical engineering principles when pilot plants are attached to R & D setups. Ideally the pilot plant must be designed by technical personnel and operated by experienced plant operators, in the presence of R & D personnel. What is occurring in your unit?

Nuclear Safety in India - lessons to learn

2011-10-06T13:39:00.000+05:30

The Nuclear Power Corporation of India Limited had conducted an extensive study on the safety of the existing nuclear power generation facilities after the Fukushima disaster. Their recommendations are given as follows:
"The four task forces after evaluating the four different designs of reactors in NPCIL fleet have come out with certain recommendations which are common to all the types of NPCIL reactors. These are:

Provision of automatic reactor trip on seismic event at all plants except where it is already available (NAPS & KAPS)
Additional Diesel operated fire tenders and diesel operated pumps to enable water addition at high and low pressures to the different systems based on the need.
Diesel driven electric generators (air cooled and not requiring external cooling) to cater to power needs.
Use of nitrogen gas from liquid nitrogen tanks to passively pressurize water tanks and transfer the water to systems at required pressure.
Provisions to use water from suppression pool except in RAPS-2
Qualifying existing water storages/tanks in the plants like deaerator storage tanks, for earthquake resistance
Conditioning signal override facility for ECCS in PHWRs where it is not available.
Additional Battery operated devices to monitor important plant parameters
Providing shore protection structures to withstand tsunami at coastal plants where they are not available
Review of Emergency Operating Procedures for external events and retraining of operator
Alternate make up provisions for spent fuel pool during extended station black out
Feasibility of providing solar powered lighting
Provision of boreholes at suitable locations to augment water supply.
Provision of suitably designed flood proof enclosure and doors for important safety related electrical power sources
Review of containment venting provisions at suitable points to vent the containment structure to stack"

Read the complete report in this link.
While appreciating the work done by the NPCIL, there are lessons also to learn from them in the field of process safety also.

Four Process Incidents

2011-10-04T08:23:00.002+05:30

A spate of process incidents have been reported in the past week.
In Kuwait, in a major refinery 4 Indian contract workers were killed due to exposure to a "gas" during maintenance work in a gas liquefaction unit. Read about it in this link.
A major fire has been reported in Dallas in a chemical mixing plant. The fire apparently overwhelmed the sprinkler system and destroyed a fire truck. Massive explosions are heard in the video. Read about it in this link. See the video in this link.
In India an explosion has taken place in a fireworks manufacturing facility killing two people. A news article in the Times Of India mentions that "This takes the number of deaths in the fireworks industries to 26 this year, making it the highest death toll recorded in recent years. The latest mishap is the fifth major accident in 2011". Read about it in this link.
In a fertilizer plant in USA, while workers were performing hot work on tank containing aqua ammonia an explosion occurred. Be very careful when doing hot work on tanks. They may appear harmless but are very dangerous! See the video in this link.

PSM and Money

2011-10-04T08:11:00.000+05:30

I am slightly changing a statement made by the great MahatmaGandhi (Earth has enough for every man’s need but not enough for every man’s greed), to suit process safetymanagement – PSM has enough for everyman’s need but not for every man’s greed! In PSM’s context, by “greed”, Imean pressure to cut costs and increase profits without looking at the processsafety consequences. Time and again, when you look at various incidents thathave occurred and continue to occur even today around the World, the fingerpoints towards cost cutting or insufficient budgets implicitly affectingprocess safety performance. Whatever model of PSM you adopt, “greed” cannot bemanaged by a system– is has to be managed by a human being and that too the onesat the top. .They can manage this only by understanding the consequences of theiractions. Not understanding the consequence of a decision that involves costcutting or even by not properly allocating and approving budgets can haveserious consequences on any process safety management system. Even though you might have implemented a system that addresses cost cutting etc, such systems have a tendency to get bypassed in times of pressure.This happens even in the "best" of companies. Any solutions???

Cathodic protection and process safety

2011-10-02T19:20:00.000+05:30

Any corrosion protection system is an integral part of maintaining process safety. One of them is cathodic protection. For a plant operator, these systems are seldom seen and operators are often not trained on the importance of these systems. A good interview by the Australian Pipeliner with Mr Mark Drager stresses the following points:
"Typically there are two types of CP systems:
Impressed – This CP system works by applying a small current (typically milliamps per kilometre) to the pipeline via units known as transformer-rectifiers. These units convert AC electricity into DC and use this electricity to lower the ‘energy’ of the pipeline. This system enables an asset owner to protect several kilometres of pipeline, provided the AC power remains connected.
Sacrificial – This CP system essentially performs a similar function via the electrical connection made between the pipeline and the buried anodes, namely zinc or magnesium. This system differs in that the DC electricity generated is due to the galvanic difference between the pipeline and the anodes. This system is also limited in protection range but is relatively maintenance free, however the anodes have a finite life and will need to be replaced.
There are few limitations to the usage of CP, but all can be overcome through careful design, construction and operation:

Excessive negative potentials;
May cause pipeline coating disbondment due to the excess hydrogen evolution;
In some instances hydrogen cracks have also developed within pipelines due to the excess hydrogen evolution;
Combined with the incorrect coating selected for the operating conditions, it may contribute to the development of stress corrosion cracks;
Interference (stray currents) from the anode bed can affect neighbouring foreign utilities if the location of the anode bed is too close them; and,
Disbonded coating or other foreign objects located next to the pipeline can cause a shielding effect. This would mean that the pipeline could not be protected locally at that point of shielding."

Read the full interview with more details in this link.

Fire in refinery

2011-09-30T18:37:00.000+05:30

A massive blaze at a Shell refinery in Singapore has been reported.
Read and see videos about it in these links:
Refinery fire 1
Refinery fire video1
Refinery fire video 2
Refinery fire video 3

Diesel tankers accident

2011-09-29T08:14:00.000+05:30

The Telegraph reports that "Fifteen tankers loaded with fuel were gutted and more than 10 lakh litres of diesel burnt when a goods train carrying them jumped tracks in Chanabana on the Bihar-Bengal border this morning.The inferno caused the tracks to melt, leading to disruption in train services on the Aluabari-NJP route.The heat from the burning fuel also scorched to death a villager, whose body was found after the flames were doused. Paddy on 500 acres along the tracks have been burnt.

The Northeast Frontier Railway (NFR) said the goods train, with 51 tankers and each of them filled with 70,000 litres of diesel from the Numaligarh Refineries Limited, was on its way to Jamshedpur from Maligaon in Assam.

Read the report (with photos) in this link.

Molten Aluminium + water = explosion

2011-09-25T11:57:00.000+05:30

An interesting theory by a scientist postulates that the twin tower collapse on 9/11 was cause by an aluminium water explosion. The article mentions the following:
"If my theory is correct, tonnes of aluminium ran down through the towers, where the smelt came into contact with a few hundred litres of water," Christian Simensen, a scientist at SINTEF, an independent technology research institute based in Norway, said in a statement released Wednesday.
"From other disasters and experiments carried out by the aluminium industry, we know that reactions of this sort lead to violent explosions." Given the quantities of the molten metal involved, the blasts would have been powerful enough to blow out an entire section of each building, he said.
This, in turn, would lead to the top section of each tower to fall down on the sections below.
The sheer weight of the top floors would be enough to crush the lower part of the building like a house of card, he said."The aluminium industry had reported more than 250 aluminium-water explosions since 1980," he said. Aluminium alloy, which in jet hulls also contains magnesium, melts at 660 degrees Celsius (1,220 degrees Fahrenheit). If heated to 750 C (1382 F), the alloy "becomes as liquid as water," Simensen said. This molten aluminium could then have flowed downward through staircases and gaps in the floor, causing a chemical reaction with water from sprinklers on the levels below.
The mix would immediately boost temperatures by several hundred degrees, releasing combustible hydrogen in the process. Such reactions are even more powerful in the presence of rust or other catalysts, which can boost temperatures to more than 1,500 C (2,700 F)."
Read the complete article in this link.

Chlorine leak incident

2011-09-25T08:51:00.004+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this incident:

Incident:
A company in Gujarat was manufacturing Chlorinated Paraffin Wax by feeding Cl2 from the 900 kgs toner in Heavy Normal Paraffins (HNP). On the day of the incident a contract labourer disconnected the empty tonner and took the fresh 900 kgs tonner in line. Immediately after taking it in line, gas started coming out from the fitting of the copper tube at high pressure. The valve of the header and tonner was attempted to be closed by wearing SCBA. But by the time the gas had already spread. Total of 34 person were affected including 15 person from one village Out of the 15 village persons,5 were minor including a 9 month old child. All the affected persons of area were admitted in hospital. The people were complaining about breathing problem, vomiting, & loose motion but their condition was stable.
Root Cause of the Incident:
· Weak copper tube and its fittings
· Not following the correct procedure of taking the filled tonner in line
· Non availability of Safety equipment near the site and extraordinarily long time for its use.
· Non competent person handling Cl2
· Inadequate facilities for Cl2 handling
· Lack of proper training to the operating persons
Action Required:
· Copper tube and its fitting are not to be kept in the open in the atmosphere. It is to be connected with the tonner immediately
· Copper tube should be 8mm I.D., 12mm O.D. and annealed for stress relief and tested at 19.9 kg/cm2 pressure
· Ammonia torch and safety equipments should be near the installation
· While connecting the tonner, the valve should be crack opened to check for leakage. In case of minor leakage the valve is to be closed immediately
· Provision of high capacity vacuum blower to be available at site. The blower to be started in case of heavy leakage in order to avoids spreading of gas
· The operating persons should be trained to wear the safety equipment particularly SCBA in shortest possible time
· In case of leakage beyond control on site/ off site emergency should be initiated
Conclusion:
· Copper tube and its fittings have limited life. Life varies from plant to plant. The tube needs to be replaced before the established Avg. life.
· Leakage must be checked from the Cl2 tonners at the time of connection/ disconnection with ammonia torch by slightly cracking the valve in case of connection and slightly loosening the connection at the time of disconnection
· Regular drills should be conducted for usage of safety equipment and critical equipment need to be provided and tested at regular intervals.

Process Safety - union's perspective

2011-09-23T18:20:00.000+05:30

The steelworkers union of USA has published an article mentioning that Oil refiners fail to learn from past safety incidents and near misses. This was published in 2009. The article mentions the following:
"OSHA is seeing the same problems repeatedly at refineries as it inspects them as part of its national emphasis inspection program. In the first year of the inspection program OSHA issued nearly 350 process safety management (PSM) citations to 14 refiners. The OSHA statement said the agency sent letters to the management of more than 100 oil refineries, providing them with data on compliance issues found under the emphasis program and urging them to comply with the (PSM) standard.
The API and industry are fighting us on the level of transparency and public reporting for process safety performance indicators.The goal of such transparency and public reporting is to allow refiners and petrochemical companies to learn from each other so accidents and catastrophic events are prevented.
This process also makes the companies more accountable to their workers and the communities where their refineries and petrochemical plants are located. It forces them to not just say they are being safety conscious, but to show they’re actually doing something about it".
Read the article in this link
UPDATE: An article published on Sept. 23rd, 2011 mentions the following:
"The lead negotiator for the UnitedSteelworkers said the union representing employees at 69 U.S.oil refineries is prepared to strike if companies don’t agree tostricter safety procedures at plants and pipelines.
The USW, which failed during contract negotiations in 2009to get companies to agree to have a USW-trained safetyspecialist at each refinery, will make a similar demand duringtalks that begin in January for a new three-year pact, Gary Beevers, a USW vice president, said today."
Read the article in this link.

Hydrogen Sulphide leak kills 4

2011-09-21T09:13:00.001+05:30

In a leak at a chemical manufacturing facility in Thane, a leak of hydrogen sulphide gas has reportedly killed 4 people. Read about the incident in this link.
In a publication made in 1996, the Oil, Chemical and Atomic Workers International Union has made a simple yet effective safety bulletin on the dangers of H2S. They also list some incidents. Read it in this link.
I have investigated fatalities involving H2S, some of them involving release of H2S when an open vessel containing sludge was moved. The trapped H2S gas under the sludge was released and killed two people. Do not take it for granted.

Explosion in Chemical Factory

2011-09-20T09:12:00.002+05:30

A news report mentions that fire and explosions in a chemical factory in Canberra made residents think that the place was being bombed! It appears that the fire and explosion was caused by transformer oil. See the news report and video in this link.

Process safety and Maintenance spends

2011-09-18T05:23:00.003+05:30

Penny wise pound foolish. If you do not maintain your assets well, you will end up paying more in the long run. Maintaining your assets not only improves process safety, it improves reliability and morale of the plant and maintenance personnel.In these days of cost cutting and lack of competency in companies, many plant managers turn a blind eye to the deteriorating assets. This also brings me to another question - how much can you flog your equipment? By debottlenecking efforts, you may increase your capacity by 30% but have you studied the effect of running on high load on the remaining plant equipment?
Read an article by Jim McCarty on "spend now, save later" in this link. It applies to chemical plants also.

Process safety and technology

2011-09-17T05:54:00.000+05:30

I have always strongly felt that technology alone cannot solve your process safety problems, its your approach towards your people and your plant that will keep you safe.
An article in the Moscow Times mentions "The United States suffered only 20 aviation fatalities in 2010, according to the Aviation Safety Database. Russia suffered 110 fatalities in the same year, the bulk of which were accounted for by the Polish Tupolev-154 that crashed in foggy conditions near Smolensk in April.
While declining to comment on the situation in Russia, one U.S. aviation professional concurred that "technology does not equal safety."
"The U.S. is lagging in air traffic control — we're using 1950s equipment and ground-based radar that means we have to fly these circuitous, occasionally inefficient routes — but it is safe," said Charles Duncan, United Airlines vice president for transatlantic, Middle East and India sales, in an interview with The Moscow Times.

"If fewer airlines meant safer skies, the world would be a much simpler place than it is," Oleg Smirnov, chairman of the Federal Transport Agency's commission on civil aviation, said in reference to government plans to slash some of Russia's hundred-plus airlines.The real problem is a misguided, laissez-faire policy of registration and approval that allows "almost anyone" to set up an airline extremely easily, Smirnov said. He also blamed a culture that promotes profits over professionalism and a blurred hierarchy of responsibility that allows companies to pressure pilots not to abort flights."

Doesn't the above sound familiar in our Chemical Industry, too? Putting profits over people and plant will not help you even if you have the latest technology. Read the full news article in this link.

Refinery cited for PSM violations

2011-09-14T19:21:00.000+05:30

A news item mentions that a refinery has been cited in the US for PSM violations. Included in the serious violations are "failing to investigate incidents as being related to process safety management, equipment repair, address inconsistent thickness measurements collected during pressure vessel inspections, maintain accurate and updated engineering drawings, and ensure that written operating procedures were certified as being current and accurate".
Read the article in this link

Dust explosions - Ignorance is Deadly!

2011-09-10T08:04:00.001+05:30

A dust explosion can be deadly. The sugar dust explosion at Imperial Sugar Industries, Port Wentworth, Georgia, USA in 2008 killed 11 people and injured 42 workers, some of them critically. Dust explosions have known to occur as far back as the 18^th century when a baker reported an explosion in a flour warehouse. Most organic materials and many metals will burn or explode if they are finely divided and dispersed in air and contact an ignition source. Dust explosions have occurred in a many industries including flour, coal, aluminum, plastic, vitamins, pharmaceutical compounds, sugar, tea, corn starch etc.A normal fire triangle consists of fuel, oxygen and ignition source. However for a dust explosion to occur, two additional elements are required – dispersion of the combustible dust in air in a concentration sufficient to ignite and confinement.Hence for a dust explosion to occur, the following are needed:

1. Fuel

2. Air (oxygen)

3. Ignition source

4. Dispersion of combustible dust

5. Confinement (The confinement causes and explosion to occur)

The above 5 elements needed for a dust explosion to occur are called a dust explosion pentagon.

The damage from a dust explosion is catastrophic because the primary dust explosion causes the loose dust present in beams and on top of other equipment to shake loose and fall down. This causes a secondary explosion which is far more deadly than the first one. Thus the domino effect of the primary dust explosion can be carried forward through elevators, conveyors and silos. The result is a catastrophic explosion. NFPA 654 states that dust layers 1/32 inch thick can create hazardous conditions.

The Material Safety Data Sheets for many substances do not indicate the potential for dust explosions. Many organisations implement changes that inadvertently create an atmosphere for a dust explosion. Enclosing an open conveyor is one such change. The Chemical Safety Board of the USA has recorded 197 incidents involving dust explosions since 1980, with 109 fatalities and 592 injuries.

Preventing dust explosions:

To prevent a dust explosion, it is necessary to eliminate the fuel (combustible dust), oxygen or ignition source.

While complete elimination of the fuel (combustible dust) may not be possible, it is possible to eliminate the chance of a secondary explosion by proper training and housekeeping. Dust collectors must be maintained properly to avoid a drop in their collection efficiency. Another method is to add an inert material like rock dust into the combustible dust.

Complete removal of oxygen is also not possible in a system comprising of conveyors, elevators, bins and silos. Inerting (use of an inert gas) also brings along safety issues of asphyxiation of personnel.

Eliminating all sources of ignition may also not be possible. Normal sources of ignition include the following:

Hot bearings and surfaces
Static electricity
Hot work (welding, cutting, brazing or spark producing activity)
Electrical system including faulty equipment

Mitigating dust explosions:

Effective mitigation requires properly designed engineering solutions. These solutions include explosion venting, explosion suppression and explosion isolation.

Explosion Venting

Explosion vents are designed to direct the gases from a dust explosion to a safe location and prevent over pressurization and damaging the equipment. The location of the vent should be placed in such a way as not to harm personnel.

Explosion Suppression

An explosion suppression system consists of a pressure or temperature sensor that detects the start of a dust explosion and a chemical suppression or inerting system that is automatically activated when the start of an explosion is detected. The chemical suppression or inerting system cools or extinguishes the flame front before it can cause damage.

Explosion Isolation

The explosion isolation systems work on the principle of detecting a dust explosion early and isolating long sections of pipelines leading to the protected equipment. A fast acting valve is used to isolate the protected equipment. The explosion venting systems are not suitable for dusts that burn quickly as the flame front speed will be high in such cases.

Pictures of the boiler gas explosion

2011-09-09T19:38:00.000+05:30

Thanks to Divyang B Shah for sending pictures of the boiler gas explosion I had mentioned two posts back. Pictures always speak a thousand words!

Generation next and Process Safety

2011-09-08T16:15:00.000+05:30

I had given a presentation on Process safety management to the Ankleshwar Chapter of Indian Institute of Chemical Engineers recently. A large number of young engineers were present. The chapter is doing good work by exposing the young engineers to the concepts of process safety management. In the audience, there were also young mechanical engineers who were working in chemical plants. We can prevent another Bhopal only by passing on the lessons learnt from Bhopal to the younger generation. The memories of Bhopal should not die with this generation but must always be kept fresh. Read my earlier post on the "Lessons from Bhopal - more so relevant today"

Boiler explosion in Gujarat

2011-09-07T16:07:00.000+05:30

"The Hindu" newspaper has reported a boiler explosion in a diary in Gujarat that has killed 7 and injured 21 others. Apparently a leaking gas pipeline was being repaired when the explosion occurred. In many companies, I have observed hot work allowed in many gas fired utility boilers and incinerators after the operators have just isolated the natural gas supply but not blinding it. In one case, the operators had isolated the natural gas to the burner of a utility boiler and removed the burner. Their argument was that they have disconnected the burner and hence no gas could get into the boiler. However, the open gas pipe (after the burner was removed) was pointing towards the boiler and when we tested the area around the pipe with a flammable gas detector, it was in flammable range. Do not depend on isolation valves alone to stop the gas from leaking through.
Read about the boiler explosion in this link.

Caustic Soda - process safety

2011-09-06T12:10:00.000+05:30

As part of their Responsible Care commitment, DOW Chemicals has published a pdf file called "Caustic Soda Solution Handbook". It contains useful data that will be required on a day to day basis for storage and handling as well as transportation. Download it from this link. (large file...be patient)

Bromine leak in Russia

2011-09-04T12:00:00.000+05:30

The BBC reports that at least 42 people received hospital treatment in the Russian city of Chelyabinsk after a leak of the toxic chemical bromine in a rail incident. Apparently about 2000 two liter glass bottles of bromine was being transported by rail and it is estimated that about 24 to 50 liters were released. Read the report in this link See a video of the leak in this link.

"Automation Addiction" in flying and its relation to process safety

2011-09-03T09:36:00.000+05:30

Joan Lowy of AP has written an article mentioning the following:
'Pilots' "automation addiction" has eroded their flying skills to the point that they sometimes don't know how to recover from stalls and other mid-flight problems, say pilots and safety officials. The weakened skills have contributed to hundreds of deaths in airline crashes in the last five years.
Some 51 loss of control" accidents occurred in which planes stalled in flight or got into unusual positions from which pilots were unable to recover, making it the most common type of airline accident, according to the International Air Transport Association.
"We're seeing a new breed of accident with these state-of-the art planes," said Rory Kay, an airline captain and co-chair of a Federal Aviation Administration advisory committee on pilot training. "We're forgetting how to fly."
Read the article in this link.

This has direct relations to the Chemical Process Industry. With so much automation in our idndustry, I am sure that operators are really forgetting their troubleshooting skills in the event of an emergency. Dr Trevor Kletz has always propounded that things must be kept simple and the way process control manufacturers are developing and implementing "solutions" for process safety, it leaves me dumbstruck. In another post, I had written that today I see operators who are becoming "procedural robots" during emergencies and plant upsets. This is a dangerous situation. Simulators do help in keeping operators skills up to date but management often thinks that it is a waste of money. Cluster simulation training ( for processes that have the same licensor) could be started, with companies pooling in for a common simulator training facility.

Counterfeit bearings and process safety

2011-09-02T07:12:00.004+05:30

An interesting article about counterfeit bearings mentions how good the counterfeiters are getting. In today's competitive environment, organisations look at cutting costs. Sometimes this may lead one to purchase a lower priced product that seems to meet all specs, but can be a counterfeit. I know of cases where wrong metal plate materials have caused incidents. Make sure you have a robust positive material identification system for your incoming items.
Read the article here. Are you bearing an unnecessary risk? Randy L. Bowen, SKF USACounterfeit bearings can lead to equipment downtime and safety problems.

Earthquakes and Process Safety

2011-09-01T18:52:00.002+05:30

The recent earthquake that hit the East coast of US has triggered a number of articles on the possibility of earthquakes in areas which are not normally earthquake prone. An article in the Economic Times mentions the following:
'Residents of the east coast of the United States generally think of themselves as safe from earthquakes. This feeling was given a jolt on August 23 when a 5.9-magnitude earthquake hit near the town Mineral in Virginia. Nobody died, but a nuclear reactor there shut down by itself as its electricity supply tripped. This nuclear plant was designed to withstand earthquakes of magnitude up to 6.2 on the Richter scale. The designers of the plant had thought that Virginia would not experience stronger earthquakes, but the tremor last week was uncomfortably close to the limit.
Central India, on the other hand, has a high degree of bulge from flexure due to stress built up from the Himalayas. Recent studies have discovered this stress as much as 1,000 km south of the Himalayas. The 1993 Latur earthquake had happened at a region of stress. This earthquake, measuring 6.4, had shocked seismologists as they had never expected an earthquake to happen there. The lessons of the recent spate of intraplate earthquakes are clear. A large portion of India lies in hazardous zones, a fact that is relevant to rapidly expanding nuclear power industry in India.
Given the ability of intraplate earthquakes to surprise, one should expect damaging earthquakes at many places in the country. Even southern cities are not entirely safe, although seismologists do not expect even moderate earthquakes to happen there. Many high-rise buildings are built without following any codes. Especially vulnerable are those on stilts and those built on or near dried lakes. The city of Bangalore is full of such buildings. So are several other cities in the country. Are we inching towards one of our worst natural disasters? "
Read the full article in this link.
A chemical plant that is not designed to the current earthquake resistance standards can be the cause of catastrophic accidents. There are large storage tanks containing highly hazardous materials in many plants and imagine the impact if their contents come out during an unanticipated earthquake!

The importance of 'O' rings in process safety

2011-08-26T08:59:00.003+05:30

I read an article about the importance of secondary seals to prevent leaks. Mr Larry Bachus, in his article mentions the following:
'About half of all pumps in the maintenance shop today were pulled out of service because they were leaking or wouldn’t hold pressure. This is most likely a leaking gasket or o-ring. The o-ring is the rubber component of most pump seals and most instrumentation fittings. The o-ring controls the temperature, pressure, and chemical limits of the device. The difference between a flowmeter in alcohol service and a flowmeter in condensate service is the o-ring. It is not the stainless steel, or the strict tolerances, or the flange bolts. The difference between a mechanical seal in ammonia service and a mechanical seal in propane service is the o-ring. The people who assemble instrumentation devices and parts for the chemical process industries install o-rings that are adequate to perform the static pressure and vacuum test on the part at the factory, which is normally done with water or air. The ultimate user must verify that the factory-installed o-rings are correct for the pumped product application (take into account temperature, pressure, chemical compatibility, and shelf life)".
Read the full article in this link.

Hydrogen peroxide accident kills two

2011-08-21T07:52:00.005+05:30

Thanks to Abhay Gujar for sending information about an accident in a chemical unit in Hyderabad tht has killed two women. As per the Times of India article, "The incident took place at 11.30am when the two workers were mixing hydrogen peroxide, methyl ethyl ketone and sodium sulphate to produce a chemical substance used in the manufacturing of asbestos sheet moulds and coolants. The high intensity of the explosion damaged a portion of the chemical unit's roof and severely injured both Venkata Lakshmi and Kalpana". Read the article in this link.

The MSDS of hydrogen peroxide warns of the following:
"Soluble fuels (acetone, ethanol, glycerol) will detonate on a mixture with peroxide over 30% concentration, the violence increasing with concentration. Explosive with acetic acid, acetic anhydride, acetone, alcohols, carboxylic acids, nitrogen containing bases, As2S3, Cl2 + KOH, FeS, FeSO4 + 2 methylpryidine + H2SO4, nitric acid, potassium permanganate, P2O5, H2Se, Alcohols + H2SO4, Alcohols + tin chloride, Antimoy trisulfide, chlorosulfonic acid, Aromatic hydrocarbons + trifluoroacetic acid, Azeliac acid + sulfuric acid (above 45 C), Benzenesulfonic anhydride, tert-butanol + sulfuric acid, Hydrazine, Sulfuric acid, Sodium iodate, Tetrahydrothiophene, Thiodiglycol, Mercurous oxide, mercuric oxide, Lead dioxide,
Lead oxide, Manganese dioxide, Lead sulfide, Gallium + HCl, Ketenes + nitric acid, Iron (II) sulfate + 2-methylpyridine + sulfuric acid, Iron (II) sulfate + nitric acid, + sodium carboxymethylcellulose (when evaporated), Vinyl acetate, trioxane, water + oxygenated compounds (eg: acetaldehyde, acetic acid, acetone, ethanol, formaldehyde, formic acid, methanol, 2-propanol, propionaldehyde), organic compounds. Beware: Many mixtures of hydrogen peroxide and organic materials may not explode upon contact. However, the resulting combination is detonatable either upon catching fire or by impact.
EXPLOSION HAZARD: SEVERE, WHEN HIGHLY CONCENTRATED OR PURE H2O2 IS EXPOSED TO HEAT, MECHANICAL IMPACT, OR CAUSED TO DECOMPOSE CATALYTICALLY BY METALS & THEIR SALTS, DUSTS & ALKALIES. ANOTHER SOURCE OF HYDROGEN PEROXIDE EXPLOSIONS IS FROM SEALING THE MATERIAL IN STRONG CONTAINERS.UNDER SUCH CONDITIONS EVEN GRADUAL DECOMPOSITION OF HYDROGEN PEROXIDE TO WATER + 1/2 OXYGEN CAN CAUSE LARGE PRESSURES TO BUILD UP IN THE CONTAINERS WHICH MAY BURST EXPLOSIVELY."

Hazards and precautions while handling sulphuric acid

2011-08-21T07:42:00.003+05:30

Sulphuric acid is used in many chemical plants. NorFalco, as part of their "Responsible Care" commitment have published a very good reference called " Sulphuric acid handbook" which is available in this link. (it is a 3.8 MB pdf file)

Fire in pesticide unit in AP

2011-08-17T15:18:00.002+05:30

Thanks to Abhay Gujar for sending info on a fire in a pesticide manufacturing unit in A.P. The article mentions the following: "In a major industrial mishap, two persons were charred to death in a fire and blast in a reactor of a pesticides manufacturing company at Cheruvukommupalem in Prakasam district in the wee hours of Wednesday.The fire broke out in the third production block at about 2.30 a.m in the third floor of the plant following suspected "electric short circuit", resulting in a blast in one of the four solvent distilling reactors at the Bhagiradha Chemicals & Industries Limited (BCIL), Revenue Division Officer K Naga Babu said. Four others working in the ground floor fled to safety".
Read the article in this link.

Distilleries are Dangerous!

2011-08-17T08:21:00.002+05:30

I have visited many distilleries in sugar plants. When compared to chemical plants, the operators knowledge of process safety is limited. In one of the distilleries, the operators were not aware of the reason why the water level was being maintained at the bottom of a flare tower. As experienced people leave the organization, it becomes all the more important for management to implement a process safety management system in distilleries. An incident in a distillery which experienced a nitric acid spill and was subsequently closed is given in this link.

Static electricity and CO2 extinguishers

2011-08-15T14:34:00.008+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this incident:
"During the plant round of Shift Incharge at Compressor House, it was observed that there is smoke and spark on Non-Drive side bearing of Cooling Tower No.1 – Pump No.D. Immediately this pump was stopped. After stopping the pump fire took place at that place which was extinguished by CO2 Fire Extinguisher. While carbon dioxide cylinder was opened for extinguishing the fire, it was observed that there was continuous spark from the surface of the horn (Outlet Black Nozzle) of the Carbon Dioxide Cylinder. This was informed to Fire Section. As per Fire Section, this is due to static current".

A safety bulletin prepared by the safety advisory group mentions the following:
"The Safety Advisory Group, SAG, has been informed of several fatal accidents caused by explosions which occurred while using CO2 during inerting equipment and storage tanks that had previously contained flammable materials. In most cases the flammable
materials were liquids or gases but dust explosions may also be triggered by the same cause.
Examples of fatalities:
• Two navy firemen were killed in an explosion while attempting to inert an 18,9 m3 Jet Fuel tank by use of portable CO2 fire extinguisher.
• Four persons were killed in an explosion on board the tanker Alva Cape while inerting naphtha tanks using CO2 cylinders.
• Twenty nine persons were killed in an explosion while witnessing the demonstration of a newly installed CO2 fire-extinguishing system for a partially filled 5000 m3 jet fuel tank, in Bitburg, Germany.
Subsequent investigations have shown that, during the inerting process, static charges of several tens of kV were generated and accumulated at the end of the piping connected to the tank. Voltage of this nature is sufficient to produce sparks which act as points of ignition for the flammable mixtures. When liquid CO2 expands up to absolute pressures of less than approximately 5 bars, the result is the formation of small particles of solid CO2 (dry ice). As the two-phase solid/gas flows through the piping, static charges are produced by the particles rubbing against other particles, between themselves, piping and equipment. Subsequently, these charges accumulate in the zones that are not earthed/grounded at the end of the pipelines, most often in valves and nozzles. The sizes of these fields, as determined by experiments, can reach values of between 50 and 180 kV/m. Similarly, static electricity can be generated by the dry ice particles after they leave the discharge nozzle.
The pressure and impurities in the CO2, equipment materials in transfer line hoses, etc. all influence the generation of static electricity".
Read the safety bulletin in this link.

Another Chlorine leakage incident

2011-08-15T13:16:00.004+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this incident:
On 18.8.2010 a message was received from Emergency Control Room regarding chlorine leakage in one of the consumers near Vadodara. Immediately the emergency team was sent to attend the problem.
PROCESS / ACTIVITY : The consumer was filling liquid chlorine from 900 kgs to 100 kgs. Cylinders by keeping on weigh balance. The tonner (900 Kgs.cap.) was pressurized with Nitrogen from upper valve. Lower valve of the tonner was connected with the withdrawal pipe fitted with filling valve to 100 kgs. Chlorine cylinder. There was a provision to release withdrawal pipe gas in 200 ltrs. drum containing caustic 100 kgs.
CAUSE OF INCIDENT: During transferring process from 900 kgs. to 100 kgs. liquid chlorine in 900 kgs. tonner exhausted. Pressure of the tonner suddenly gone up due to nitrogen padding. This resulted in very heavy vibration in the withdrawal pipe. Due to this, connection at the both ends was disturbed and damaged the corroded fittings and filling valve due to physical impact. This resulted in heavy gas release from the tonner and cylinder side.
ACTION TAKEN :

Both the valves of 900 kgs. tonner and 100 kgs. Cylinder were closed after wearing the SCBA (Self Contained Breathing Apparatus).
Fire hydrant team sprayed water externally to restrict gas in the outer area.
Police Deptt. controlled the external public for further exposure.
10 persons affected with gas during the process were admitted in the hospital which were discharged after first aid.
Spilled chlorine hydrate was neutralized with Caustic Soda gradually.
All the tonners were brought back to the plant as per the advise of Explosive Deptt. and depressurized.

All the tonners condition and valves were checked and found perfectly in working order. TECHNICAL / LEGAL LAPSES :

Filling of liquid chlorine from 900 kgs. to 100 kgs. was not authorized from Deptt. of Explosives.
900 kgs. Tonner was pressurized manually with Nitrogen pressure from cylinder (max. pressure 150 kg/cm2).
Max. pressure required to transfer liquid chlorine to toner is about 10 – 11 kg/cm2 where as uncontrolled pressure was applied manually. It disturbed the transfer process due to high pressure in tonner.
There was no well set chlorine neutralizing system. Neutralization was done in 200 ltr. Drum containing caustic.
Brazing of copper tube and chlorine valve used for filling was badly corroded and brazing workman ship was very poor. The fitting was not tested at desired pressure.
No safety equipments were maintained by the consumer to control any emergency.

LESSONS LEARNT :

Filling of liquid chlorine into the tonners can be done after getting the necessary approval from the Deptt. of Explosives.
A well set system has to be provided for filling and neutralizing from safety point of view. It is a very unsafe process to transfer liquid chlorine without proper facilities and competent persons
Corroded fittings are not be used. Withdrawal pipes needs to be tested and replaced regularly.
Provision of pressure regulator and pressure gauge in the line / header is a must.
All the safety equipments and gas mask should be readily available.
Provision of vacuum system connected with chlorine neutralization system can help to control chlorine hydrate gas due to liquid chlorine spillage.

Electrical area classification

2011-08-13T09:40:00.004+05:30

Many plant operations, electrical maintenance and process engineers often get confused about electrical area classification. Electrical area classification is an important part of process safety. Read a succinct explanation of electrical area classification in this link.

Process safety and security - facility siting

2011-08-11T08:51:00.004+05:30

A news article mentions the presence of a warehouse containing ammonium nitrate near refineries and fertilizer plants in Visakhapatnam. Recently, the Govt. of India has recently brought Ammonium Nitrate under the explosives act after its usage by terrorists.
The article mentions the following:
"At the time of setting up of this facility in 2007, there was a furore. After the environment assessment report was presented before the MoEF (ministry of environment and forests), the matter went for public hearing, which saw many local residents protesting storage of this hazardous substance, backed by some political parties as well. "But like in many other cases, public objection was overlooked and the government cleared the project, which is again illegally built on the CRZ (costal regulation zone) area," said Mr Sarma.
"Vishakhapatnam is a busy and an important area," he added, "it is a major Coromandel port, it houses the headquarters of the Eastern Naval Command, is an ecologically sensitive zone and is an industrial and commercial hub. Several incidents—from the 26/11 massacre to the sinking of MV Rak—have shown us how vulnerable our coastlines are. In such a situation, storage of explosive substances like ammonium nitrate is a big risk, especially when there are no checks on it."
Read the article in this link.

The importance of lube oil

2011-08-08T09:21:00.003+05:30

Many process incidents have been initiated by a shutdown of a critical equipment due to problems in the lube oil system. A short but good article titled "3 reasons why lube oil fails" written by Jeremy Wright highlights contamination, oil degradation and additive depletion as the 3 reasons why lube oils fail. Read the article in this link.

Hydrogen cylinder fire incident

2011-08-07T14:17:00.001+05:30

A fire in a plant in the US where hydrogen cylinders on a trailer caught fire has been reported. See the photos of the fire in this link. Apparently a supply line was being repaired at the time of the incident.

Sodium nitrite explosion kills 2

2011-08-06T09:40:00.001+05:30

A blast in an disinfectant manufacturing unit in China has reportedly killed two persons. The unit uses sodium nitrite. A fire is reported to have caused the explosion. The MSDS of sodium nitrite mentions the following:
"Special Remarks on Fire Hazards:
When in contact with organic matter, it will ignite by friction. May ignite combustibles.
Special Remarks on Explosion Hazards:
Explodes when heated over 1000 F (538 C). Sodium Nitrite + thiocyanate explodes on heating. A mixture of sodium nitrite and various cyanides explodes on contact. Mixture of sodium nitrite and phthalic acid or anhydride explode violently on heating.Fusion of urea with sodium nitrite Interaction of nitrites when heated with metal amidosulfates (sulfamates) may become explosively violent owing to liberation of nitrogen and steam mixed with ammonium sulfamate form. Violent explosion occurs if an ammonium salt is is melted with nitrite salt. Shock may explode nitrites. must be carried out exactly as described to avoid risk of explosion".
Read the news article in this link.
See the MSDS of sodium nitrite in this link.

Do awards and certifications help process safety management?

2011-08-06T09:23:00.009+05:30

I have been hearing about incidents in India (some fatal) in organisations that are recognized by their peers or have been awarded certificates and awards for their safety performance. Receiving awards and logos is one thing and making a continuous 24X7 commitment to process safety is another. A friend was mentioning about an incident in an organisation in India,which has all the certifications and peer recognitions in place, where a reactor exploded killing few persons. The reaction which was highly hazardous in nature was apparently being carried out manually. During the end of the shift, the operator noticed that the reactor's steam jacket valve was passing, but apparently failed to communicate this to his relief operator. The temperature increase caused a runaway reaction to occur destroying the reactor (details about pressure relieving devices are not known) . My friend visited the unit a few months after the incident and he observed that many of the employees were not even wearing basic PPE!

I have also visited organizations in India where process safety is managed excellently and is ingrained into their way of work. What I noticed in these organizations is that most of them do not go for external recognitions but concentrate on getting their house in order on a daily basis.A good process safety management program's reward is judged by NOT having process incidents and process near misses.

Hazards of Nitrogen trichloride

2011-08-05T18:13:00.000+05:30

Thanks to Mr Harbhajan Singh Seghal who has shared his presentation in the World Chlorine programme in Brazil last year, about the hazards of nitrogen trichloride in the chlorine manufacturing industry. Quoting from his presentation, "Nitrogen Tri-Chloride is one of the most hazardous material in Chlor-Alkali industry. Fatalities have occurred and workers have been injured by NCl3 explosions.The explosive power of small quantity of NCl3 can be catastrophic & can cause release of Chlorine & large scale damage to personnel, plant equipment . NCl3 is sensitive to light, impact and ultrasonic radiation. A spontaneous explosive compound, Explosive potential is 30% of TNT".
See his presentation in this link

Chlorine incident

2011-08-04T14:50:00.002+05:30

Thanks to Mr Harbhajan Singh Seghal for sending this case study:
CASE STUDY OF CHLORINE LEAKAGE

INCIDENT :

Chlorine leakage took place from the bottom of 100 Kgs. chlorine cylinder at one of the water chlorination plant situated in a populated area.
ACTION TAKEN :
- The consumer informed the FIRE BRIGADE and the manufacturer.
- Fire brigade reached the site at the earliest and the manufacturer reaches after 1.5 hr. being 100 km away. By the time situation was under control.
- Fire brigade put the leaking cylinder in the underground pit with MANHOLE.
PROBLEM EXPERIENCED IN CONTROLLING CHLORINE LEAKAGE:
- The cylinder started floating on the surface of water in the pit and gas started coming out from the MANHOLE.
- Additional weights were tied with cylinder to keep it dipped.
- Additional water had to be pumped as still some gas was coming out.
- It took about one hour to control the situation in the populated area. No body in the area was affected
OBSERVATIONS:
- The cylinder was 15 years old
- It was tested hydraulically 20 months earlier.
- Pitting & dents were observed at the bottom side near the STAND.
- Pin hole had developed in the pitting area near the welding of the stand.
- There was no safety equipment, neutralizing system with the consumer.
- No proper loading / unloading system of Cl2 cylinder was there.
- No provision of Ammonia torch / ammonia was there to check leakage during connection / disconnection stage. Corrosion was observed in the chlorination system.
POSSIBLE REASONS OF LEAKAGE:
- Some moisture in the cylinder before filling or backflow of moisture after getting the cylinder empty due to inadequate barometric leg or malfunctioning of chlorination system can result pinhole.
- Unloading of the cylinder by dumping on the ground results dent and makes the surface weak and some times develops pin hole.
- Storage of the cylinder at wet and muddy place excel rate corrosion in the cylinder surface.
- Old cylinders were designed as per Ammonia cylinders code which has tolerance of scattered porosity in the plate of the cylinder & welding against NIL porosity in the present standard IS-3196. Minor leakages were observed in such cylinders also at any time. Now, the permission is not given to such cylinders, only latest code is followed.
- Most of the consumers are withdrawing Cl2 at higher rate which results ice formation on the outer surface of the cylinder. Also gas nuisance is observed in the area due to poor connection or bad MOC particulars gaskets. In the presence of moisture & gas nuisance, chlorine cylinders and Cl2 valves are badly affected and results emergency sometime.
- Most of the consumers do not keep Ammonia Torch at site and not checking leakage at the time of connection / disconnection and on regular basis. This overlooking also causes chlorine leakage beyond control.
SUGGESTED ACTIONS :
- Cylinders are to be stored at concrete flooring under a covered shed. These should be loaded / unloaded with the help of hoist / chain block / on the plate-form to avoid any damage.
- Ammonia Torch should be kept nearby. No leakage should be allowed.Two to Three times leakage should be checked in the shift.
- Extra precautions to be taken while filling cylinder in checking moisture, physical examination of cylinder & painting etc. Cylinders with external pitting / dents should be rejected . Consumer should provide barometric leg in their system.
- Consumers need to be educated for safe handling of chlorine from time to time. Consumers should have all safety equipments, chlorine neutralizing system and competent persons.
- In case of leakage cylinder / tonner is not to be put in water. It results higher chlorine release due to poor solubility of chlorine in water and cause serious emergency. It should be handled by vacuum blower & neutralizing system only.
- At the first site leaky part of the cylinder / tonner should be brought on the upper side. This results reduction in Cl2 leakage by 15 times. By increasing the consumption rate of chlorine after above action, lowers the temperature / pressure of the cylinder and results further reduction in leak rate and gives some relief time for emergency action.
CONCLUSION :
- Cl2 leakage can be handled safely by competent persons with the help of safety equipments and chlorine neutralizing system.
- Cl2 handling system need to be audited and persons need training from time to time.
- Standard guide lines are to be followed for safe handling of chlorine.

Three killed by CO leak in steel plant

2011-08-04T06:56:00.000+05:30

The Deccan Herald has reported an incident in a steel plant in Bellary, where three people were killed due to CO leak. The article mentions

"Three workers, including an assistant manager, died on the spot after inhaling carbon monoxide at the Jindal (JSW) steel factory at Toranagal in Bellary district early Tuesday morning.

Lack of precautionary measures is the cause of the incident, said District Superintendent of Police Dr Chandragupta, who visited the spot. A case has been registered at the Toranagal police station. The incident occurred when the trio came to the gas container at the blast furnace unit 2 of the energy management division (EMD), climbed down into the ‘U’ seal pot and turned the valve on to check the pipeline. The three men had gone to check the gas container on getting information from the control room that the gas level had slumped". Read the article in this link.

Insulation can burn!

2011-08-03T08:20:00.001+05:30

Abhay Gujar has sent news about an insulation fire in a shoe factory in Hanoi, that killed 17 people. According to the news article, "The welder was installing a lightening rod on the factory's tin roof in preparation for a tropical storm that is expected to hit northern Vietnam later Saturday. The insulation fell to the factory floor in a fireball, blocking the 150-square-metre workshop's only entrance before quickly engulfing piles of shoemaking materials, it said".
Some insulating material can burn. Make sure you read the MSDS of your insulating material before attempting any hot work.

Handle waste with care

2011-08-03T08:15:00.000+05:30

Waste chemicals can cause major issues if not handled properly. In 2007, an explosion took place in an waste aerosol can shredder unit in the UK An article about the incident mentions the following: "The HSE discovered that the machine had not been designed to safely shred waste containers containing residues of flammable liquids and gases. Furthermore, unsafe operating procedures were in place".
The general human tendency when dealing with the ETP or waste handling is NOT to treat as seriously as an operating plant. With many waste treatment facilities being outsourced, make sure that you have robust systems in place to avoid incidents.

Read the article in this link.

Risks while attending to an emergency

2011-07-29T21:08:00.000+05:30

A friend has sent details of an incident in an onshore oil well which experienced a fire. When the operations team went in a vehicle to isolate the well, they had to cross a oil spill on the track. While doing so, the vehicle caught fire and 5 personnel died.
This incident highlights the need to address all possible scenarios in your drills. No drill can be the real thing but better be prepared for the worst.

Warnings before a disaster

2011-07-27T18:47:00.000+05:30

An article by Reuters on the Fukushima nuclear disaster highlights the fact that no accident comes without warning. There will be enough signals that an accident is about to happen but we may ignore it either out of risk blindness or pressure on production. The article highights the following about the Fukushima disaster: Cost saving culture, complaceny setting in and maintenance philosophies for older plants. All the points are applicable in the chemical industry, too.
Read the article in this link