February 28, 2011

Know the chemicals you deal with

An incident took place when phosphoric acid was inadvertently unloaded into a storage tank containing 12.5% Sodium Hypochlorite solution. The resulting chemical reaction of the two caused a chlorine gas release which affected the field operator. In another incident, a chemical that could be thermally decomposed was inadvertently stored near a steam pipe. The resulting heat transfer from the steam pipe caused a thermal decomposition later caused a fire in the warehouse in which the chemical was stored. Many of us do not treat chemicals with the respect they deserve. MSDS need to be understood by the people who handle chemicals. It is not just a matter of pasting the MSDS in the place where the chemicals are stored. it is a matter of understanding them.

February 25, 2011

Accident to truck carrying hydrogen cylinders

Thanks to Abhay Gujar for sending this information - A truck carrying 180 hydrogen cylinders overturned due to a burst tyre in an highway (NH-8) resulting in the drivers cabin catching fire. Luckily, the cylinders did not explode. Now, the motor vehicle rules clearly specify the rules for dangerous cargo, including fitness of the vehicle carrying it. If you are transporting cylinders through trucks, ensure that the vehicle is in roadworthy condition. Imagine what would have happened if all the 180 cylinders overheated and burst!
The local news article link is attached.

February 24, 2011

Temporary solutions - permanent problems!

Management of change is the most difficult element to implement as it requires a lot of commitment to make it work. Very often, temporary changes can have a devastating effect. A safety officer mentioned to me about a temporary electrical cable that was laid across an internal road. To protect the cable, it was inserted through a metal pipe. The cable was energised and work was going on. However, the a portion of the pipe was damaged and a piece of the metal was actually cutting into the cable everytime a vehicle moved over the pipe. Luckily an alert fitter noticed this and an incident was avoided. Do not take the temporary route or shortcuts in process safety.

Read about a boiler explosion that occurred due to a temporary change in this link.

February 22, 2011

A Bhopal in the USA?

An article highlights the possibility of a bhopal type disaster happening in the US. The article mentions the following:
"Bhopal should have been a wake up call, but it is unclear whether chemical plants around the world are any safer a quarter century after the December 1984 disaster—during which some 40 tons of toxic methyl isocyanate gas leaked from a pesticide plant owned by Union Carbide (now part of Dow Chemical), killing 2,259 people immediately and causing lifelong health problems and premature death for tens of thousands more.
In the U.S., the Occupational Safety and Health Administration (OSHA) oversees chemical and other facilities that deal with hazardous materials, making sure various “process safety” routines are followed so as to “prevent or minimize the catastrophic injury or death that could result from an accidental or purposeful release of toxic, reactive, flammable or explosive chemicals.” Also, in the wake of the 9/11 attacks, the U.S. Department of Homeland Security instituted its own “Chemical Facility Anti-Terrorism Standards” (CFATS) that chemical and other hazardous materials facilities must follow or be shut down.
While this system has worked pretty well in the U.S. so far, some worry that a Bhopal-scale tragedy, whether due to an accident or terrorist attack, could still occur on American soil. For one, water treatment and port facilities are exempt from CFATS altogether, so some of the nation’s largest chemical facilities are not subject to as rigorous standards as they could be. A 2009 bill that passed the House of Representatives but failed to make it through the Senate addressed this and other issues. Supporters are optimistic that the bill in one form or another could resurface in future legislative sessions".

Read the article in this link

February 21, 2011

And the Flare goes "BOOM" at night!

When I was working in the Middle East, we had a 80 m tall flare that sat in the middle of the plant. After a few years we started hearing "BOOM" noises from the flare when the plant was running normally. The noise was heard more often at night. The "BOOM" used to be muffled and there was no external evidence of an explosion in the flare and the plant continued to operate without interruption. We did a lot of investigation and finally caught the culprit that was allowing air into the system. Treat your flare systems with respect. They are mute spectators when everything is normal but can save the day during an emergency!
For a good presentation on flare systems see this link

February 17, 2011

The Buncefield Investigation - be prepared to see similar findings elsewhere

The HSE, UK has published the investigation report of the explosion and fire that occurred in the Buncefield oil depot in the UK, in December 2005. The main findings are quoted below:
"Fundamental safety management failings were the root cause of Britain's most costly industrial disaster, a new publication reveals.
  • Systems for managing the filling of industrial tanks of petrol were both deficient and not fully implemented
  • An increase in the volume of fuel passing through the site put unsustainable pressure on those responsible for managing its receipt and storage, a task they lacked information about and struggled to monitor. The pressure was made worse by a lack of necessary engineering support and other expertise.
  • A culture developed where keeping operations going was more important than safe processes, which did not get the attention, resources or priority status they required.
  • Inadequate arrangements for containment of fuel and fire-water to protect the environment.
 The 36-page report highlights a number of process safety management principles, the importance of which were underlined by the failings at Buncefield:
  • There should be a clear understanding of major accident risks and the safety critical equipment and systems designed to control them.
  • There should be systems and a culture in place to detect signals of failure in safety critical equipment and to respond to them quickly and effectively.
  • Time and resources for process safety should be made available.
  • Once all the above are in place, there should be effective auditing systems in place which test the quality of management systems and ensure that these systems are actually being used on the ground." 
In only few organisation do I see the above 4 points religiously followed. In all of them, there is a common link - the person at the top is a person with a hardcore chemical engineering background and plant experience. In all other cases, the top management are persons without such experience and incidents continue to happen. In such cases, the organization must ensure that a person with proper experience should be in a position to act as a link between top management and the plant. While on the same subject, today LOPA has become a fashionable word for many managements but they do not realize that once a LOPA study is carried out and recommendations implemented, they should be maintained for the complete life cycle of the plant. For this it requires resources and manpower and  these are often found wanting. Keep your fingers crossed!!
Read the HSE report in this link.

February 16, 2011

Hazards of low oxygen inside confined spaces

I got this information from a safety officer of a large company that happened in his company 20 years ago. A vessel had to have its rubber lining repaired. The adhesive used for holding the lining to the solvent was expensive and the contract labourers who were handling it were told to handle it carefully and not to spill it. However, when one contract labourer was entering the vessel by a ladder, he inadvertently lost grip on the open can of adhesive and it fell down to the floor of the vessel. In order to cover up his mistake, he and another co-worker entered the vessel quickly and tried to apply the adhesive to the walls of the vessel. Due to the sudden increase in adhesive concentration in the confined space, the oxygen level decreased and both died of asphyxiation.
Today there are accidents that still continue to happen on the above lines. Learn from history. Do not allow more people to die.

February 14, 2011

Another natural gas explosion

The aging natural gas pipeline network in the USA has experienced another pipeline explosion. This explosion has killed 4 persons. Authorities are trying to determine whether an determine whether a 83-year-old cast-iron gas main or its feeder lines was the source of the explosion. A news article mention the following:
"The fiery blast late Wednesday night was the latest deadly natural-gas disaster in recent months to raise questions about the safety of the nation's aging, 2.5-million-mile network of gas and liquid pipelines.The explosion, which flattened a pair of rowhouses and set fire to a block of homes, occurred in an area where the underground gas main lacked shut-off valves. It took utility workers five hours of toil in the freezing cold to punch through ice, asphalt and concrete and seal the 12-inch main with foam, finally cutting off the flow of gas that fed the raging flames.An Associated Press investigation published Saturday found that many pipelines around the country are not equipped with remotely operated or automatic shut-off valves that can quickly stop the flow of gas in an accident, even though federal safety officials have recommended such devices to industry and regulators for decades".
Read the article in this link.

February 13, 2011

Preventing fires in thermal fluid systems

Many chemical industries use variety of thermal fluids for their reactor heating/cooling systems. There is often a lack on the part of the user on the hazards of the thermal fluids and the importance of proper specification and maintenance. Most of the thermal fluid systems operate above their flash points. I read some good technical papers by Paratherm Corporation. Excerpts from the articles are given below:
"Fluid leaking from valves, gasketing,welds or instrument ports finds its way into porous insulation and wicks through. Remaining as hot as the system itself, the fluid comes into intimate contact with the air in the insulation's millions of pockets. As it enters each pocket, the fluid oxidizes and decomposes—in the process using up the existing air and creating heat. Confined within the insulation, the heat has little chance of escaping. The continued oxidation causes temperatures to rise. In some cases temperatures may exceed the autoignition point of the fluid. Should the insulation be opened up when the system is hot, fresh air will immediately enter. Coming into contact with the hot, partially oxidized fluid, fresh air can cause spontaneous ignition resulting in a smoldering fire, or a flash".
The paper also recommends precautions to be taken in component selection, installation and maintenance.
Read the paper in this link. Read another article on Prevent fires in thermal fluids

Disclaimer: I am not advocating any product and am sharing this information in the interest of process safety

February 12, 2011

CSB safety videos

I am quite surprised at the lack of awareness of personnel in the chemical industry about the good work the Chemical Safety Board of the US is doing. The CSB is an independent federal agency investigating chemical accidents to protect workers, the public and the environment.
They have many free safety videos on their website which should be shown to every person in the chemical industry. The videos are available in this link.

Hydrogen gas detection in refineries

I chanced upon a good article written by Gassonic on hydrogen gas detection in refineries. The article mentions the following:
"There are several hazards associated with hydrogen, ranging from respiratory ailment, component failure, ignition, and burning. Although a combination of hazards occurs in most instances, the primary hazard with hydrogen is the production of a flammable mixture, which can lead to a fire or explosion. Because its minimum ignition energy in air at atmospheric pressure is about 0.2 mJ, hydrogen is easily ignited. In oil refineries, the first step in the escalation of fire and detonation is loss of containment of the gas. Hydrogen leaks are typically caused by defective seals or gaskets, valve misalignment, or failures of flanges or other equipment. Once released, hydrogen diffuses rapidly. If the leak takes place outdoors, the dispersion of the cloud is affected by wind speed and direction and can be influenced by atmospheric turbulence and nearby structures. With the gas dispersed in a plume, a detonation can occur if the hydrogen and air mixture is within its explosion range and an appropriate ignition source is available. Such flammable mixture can form at a considerable distance from the leak source.
In order to address the hazards posed by hydrogen, manufacturers of fire and gas detection systems work within the construct of layers of protection to reduce the incidence of hazard propagation. Under such a model, each layer acts as a safeguard, preventing the hazard from becoming more severe.The detection layers themselves encompass different detection techniques that either improve scenario coverage or increase the likelihood that a specific type of hazard is detected. Such fire and gas detection layers can consist of catalytic sensors, ultrasonic gas leak monitors, and fire detectors. Ultrasonic gas leak detectors can respond to high pressure releases of hydrogen, such as those that may occur in hydrocracking reactors or hydrogen separators. In turn, continuous hydrogen monitors like catalytic detectors can contribute to detecting small leaks, for example, due to a flange slowly deformed by use or failure of a vessel maintained at close to atmospheric pressure. To further protect a plant against fires, hydrogen-specific flame detectors can supervise entire process areas. Such wide coverage is necessary: Because of hydrogen cloud movement, a fire may be ignited at a considerable distance from the leak source".

Read the article in this link (pdf file -be patient)

Disclaimer: The reader is recommended to to do a survey before purchasing detectors.

February 10, 2011

Natural gas pipeline explosion and ethanol rail tankers derailing incidents

Thanks to Abhay Gujar for sending this info. A major fire has been reported in a natural gas pipeline explosion in a plant in Texas. One Worker was killed. Read about it in this link.
Another incident involved the derailment and catching fire of ethanol rail tankers near Ohio. The article mentions that "Twenty-six cars of a 62-car Norfolk Southern train jumped the tracks at about 2:20 a.m. in Cass Township, and the contents of those that ruptured in the impact caught fire. The denatured ethanol in other tank cars that were not breached immediately was heated by the flames until it boiled and the tanks could no longer withstand the pressure, causing explosions that sent fireballs bursting spectacularly into the sky".
Read the article in this link.

Students campaign - "Crackdown on cracking crackers"

I was happy to receive a mail from Arijit Chanda, a student of Pondicherry Engineering College regarding assistance for a campaign they were planning to create awareness about the safety in firecracker bursting and avoidance of child labour in their manufacture. Though I could not contribute to their cause, I was happy to hear from him that their campaign went off well and was reported in the Hindu. The article in the Hindu about their campaign is given in this link. Kudos to Arijit and the team!

February 9, 2011

Exothermic explosion causes serious injury

A news article mentions that a 58 year old man was seriously injured when he was was in the process of mixing sodium cyanide pellets with hydrogen peroxide at a Chemical plant, when the volatile solution exploded, soaking him in the hot toxic mixture.
"An investigation by the HSE revealed that approximately five times too much hydrogen peroxide was added to the sodium cyanide pellets which resulted in an exothermic explosion".
Train your workers on the hazards of inadvertent reactions. Read the article in this link.
Read another article about the same incident in this link.

February 8, 2011

Another tragic confined space entry fatality - train your workers about the hazards

The Indian Express has reporetd a confined space entry fatality in a chemical factory near Pune. Apparently, a worker entered the confined space without any protection,after the can from which he was adding adhesive fell into the vessel. He got inside the vessel and was then overcome by the toxic fumes. Another worker who entered to save him was seriously injured. The rescue crew had to cut an opening in the vessel to rescue the trapped persons. It is sad that the vessel was not designed as per standards with manholes of standard dimensions. How many more lives will be lost in confined space accidents? It is important to train your workers on the hazards of confined spaces and requirements for a confined space entry permit. Also, train your people to overcome the urge to enter a confined space to rescue a fellow worker, without proper protection. It is a natural human tendency to enter a vessel quickly to save a fellow colleague, but it is a very dangerous practice if proper respiratory protection is not worn. Read more in this link.

In another incident that occurred some time back, a young engineer in a fertiliser plant in India was killed when he slipped into a vessel under nitrogen atmosphere. He was trying to check the work done inside the vessel from outside when he reportedly slipped inside.

February 6, 2011

Buy the Practical Process Safety Management book and support the Bhopal Victims

To all my readers - The National Safety Week is coming up in March and I would appreciate it if you could purchase copies of my book "Practical Process Safety Management" (details given in this link) to present to winners of safety week contests. As you are aware, the proceeds from this book are donated to the surviving victims of Bhopal and your contribution would make a difference.

Contact me at bkprism@gmail.com for details of purchasing the book. Thanks in advance!

Major fire at MIDC Taloja -Dangers of handling solvents

Thanks to Abhay Gujar for sending information about this fire:
There has been another Major Fire in one more Chemical Unit located in Taloja - M.I.D.C, near Navi Mumbai on Wednesday, 2nd February 2011.This is a Second Major Fire in Taloja M.I.D.C after the recent ‘Major Fire’ at ‘IOCL, Lube Blending Plant’ - on 18th January 2011. The fire was reported to have been fed by solvents stored in cans. Read the news article in this link.

The American Chemistry Council has published an excellent technical guide on solvent handling which highlights the following when handling solvents::
• "Understand the Solvent
• Follow Appropriate Regulations and/or Standards Applicable to Handling and Storage of Solvents
• Address Potential Ignition Sources
• Understand Conditions for Autoignition
• Maximize Ventilation as Appropriate to the Application
• Maintain Appropriate Work Temperature
• Educate and Train Employees
• Report Leaks and Spills in Accordance with Federal and State Regulations
• Consider Providing Secondary Containment Solutions
• Develop Appropriate Loading and Unloading Procedures
• Consider Developing an Emergency Plan
• Consider Inert Storage Solutions
• Consider Developing Standard Operating Procedures
• Control Static Electricity
Examples of operations that can generate static charges:
• High velocity and turbulent conditions, for example in pipelines, or the discharge of jets from nozzles and tank mixing.
• Filtration, particularly through micropore elements.
• Liquid droplets or foam falling through a vapor.For example, a spray or mist formation in vapor
spaces, splash filling of tanks, tankers, drums or intermediate bulk containers.
• Settling water droplets through liquid hydrocarbon. For example, after a line has been pigged off into a tank with water.
• Bubbling of gas or air through liquids.
• Mechanical movements such as belts or pulleys used as air blast coolers.
• The movement of vehicles, fans or even people.
• Movement or transport of powders, although not relevant in the case of solvents. There have been many incidents involving materials such as flour, where static accumulation has caused an explosion of flour dust.
• High velocity release of steam to atmosphere."

Read the ACC technical guide in this link.

February 5, 2011

Dangers of natural gas blowing -CSB Video

The CSB has released a new video on the dangers of purging with natural gas. I observe that though personnel in chemical plants and refineries are aware of the hazards, a number of other industries that use natural gas are unaware of the hazards. These include power plant operators. It is common sense that fuel+oxygen+ignition source = Fire. However, common sense is not so common, so educate the people who are not normally trained in the hazards of natural gas.
See the CSB video in this link.

Recipe for a dust explosion

I chanced upon a newsletter by Fike Corporation written in 1997. This was way before the Imperial sugar dust explosion incident in 2008. Its a pity that though the potential for dust explosions are known for a very long time (more than 50 years), still these explosion continue to occur. Salient points form the article are quoted below:
"Combine complacency with lack of housekeeping and you have the perfect recipe for a dust explosion.
At too many facilities, the ingredients are already there. All you need is a building with layers of combustible dust, like corn starch. Add unvented equipment that draws in suspended dust. Let a few airborne particles stray and find a spark. The first explosion will rupture the equipment, tossing the building dust into the air. The second will probably collapse the walls. And, if by chance you attached a sprinkler riser to one of the load bearing walls, forget your sprinkler protection. It’s gone. A suspended, combustible dust cloud burns much more violently than a pile of sawdust. When suspended dust particles are completely surrounded by oxygen, they rapidly release a tremendous amount of energy. The pressure wave produced by the initial exploding dust cloud shakes and suspends more dust from other surfaces to fuel a chain reaction of violent explosions. Usually, the second or third explosion is worse than the first.Industries producing dust as a product, such as some pharmaceutical industries, tend to be more aware of the hazards than industries that produce dust as a by-product. Unfortunately, it’s very easy for personnel to overlook the fallout from operations, such as grain handling or furniture making. Then an explosion hits, endangering the facility and equipment as well as the employees".

Read the newsletter in this link.

February 2, 2011

Major fire in Panoli Dyes Pigment unit

Thanks to Ajay Pancholi for sending this information - Times of India has reported a major fire in a Panoli Dyes pigment unit. Its is reported that several firefighters were hospitalised as they were injured when chemical drums (barrels) exploded in the fire. The cause of the fire is being investigated. The chemical involved is reported to be hexene. Read the MSDS of hexene in this link.
In many chemical units especially in small scale sector, flammable chemicals are handled in drums to save storage costs. A flammable chemical stored in a drum is a potential time bomb. The more number of full drums you store, the more is the hazard. It is better you do a monthly drum safety audit to ensure that good work practices are followed. In times of production pressure, managers tend to ignore the hazards of filled chemical drums.
Read the article about the fire in this link.

Gas leak at chemical factory kills three

A newspaper report mentions that 3 people were killed in a gas leak from a chemical factory in Uttar Pradesh. A chemist has been detained for interrogation. The plant in question reportedly has a thiophosgene plant and serves many pharma plants.
Read the article in this link.

Plate heat exchangers and hazard free operations

In many processes plate heat exchangers are used. We tend to take them for granted when compared to shell and tube heat exchangers. They are reliable if they are properly specified and installed. A good article highlights the main points to have a trouble and hazard free operation. The article mentions the following tips:

"TIP 1: Tell Them Everything
TIP 2: Check Compatibility
TIP 3: Avoid Situations Where Pressure Spikes Can Occur
TIP 4: Use a Strainer or Bypass the Unit During Startup
TIP 5: Keep Large Particles Out
TIP 6: Periodically Check Plate Pack Dimensions and Frame Integrity
TIP 7: Use Good Piping Practices
TIP 8: Take Precautions to Minimize Port Erosion
TIP 9: Design for the Future, But Purchase on Your Current Needs

TIP 10: Purchase OEM Parts to Avoid Warranty Problem"

Read the article in this link.