PSM and Money

I am slightly changing a statement made by the great Mahatma Gandhi (Earth has enough for every man’s  need but not enough for every man’s greed), to suit process safety management – PSM has enough for every man’s need but not for every man’s greed! In PSM’s context, by “greed”, I mean pressure to cut costs and increase profits without looking at the process safety consequences. Time and again, when you look at various incidents that have occurred and continue to occur even today around the World, the finger points towards cost cutting or insufficient budgets implicitly affecting process safety performance. Whatever model of PSM you adopt, “greed” cannot be managed by a system– is has to be managed by a human being and that too the ones at the top.  .They can manage this only by understanding the consequences of their actions. Not understanding the consequence of a decision that involves cost cutting or even by not properly allocating and approving budgets can have serious 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

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

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

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

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

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

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 United Steelworkers said the union representing employees at 69 U.S. oil refineries is prepared to strike if companies don’t agree to stricter safety procedures at plants and pipelines.
The USW, which failed during contract negotiations in 2009 to get companies to agree to have a USW-trained safety specialist at each refinery, will make a similar demand during talks 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

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

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

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

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

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!

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

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

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

"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

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

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

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

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

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

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

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

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

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!

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

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

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 :

1. Filling of liquid chlorine from 900 kgs. to 100 kgs. was not authorized from Deptt. of Explosives.
2. 900 kgs. Tonner was pressurized manually with Nitrogen pressure from cylinder (max. pressure 150 kg/cm2).
3. 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.
4. There was no well set chlorine neutralizing system. Neutralization was done in 200 ltr. Drum containing caustic.
5. 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.
6. No safety equipments were maintained by the consumer to control any emergency.

LESSONS LEARNT :

1. Filling of liquid chlorine into the tonners can be done after getting the necessary approval from the Deptt. of Explosives.
2. 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
3. Corroded fittings are not be used. Withdrawal pipes needs to be tested and replaced regularly.
4. Provision of pressure regulator and pressure gauge in the line / header is a must.
5. All the safety equipments and gas mask should be readily available.
6. Provision of vacuum system connected with chlorine neutralization system can help to control chlorine hydrate gas due to liquid chlorine spillage.

Electrical area classification

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

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

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

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

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?

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

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

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

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!

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

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.