March 9, 2012

Rupture of a rubber lined vessel

A rubber lined vessel was taken out of service to replace the rubber lining. The vessel was taken to the rubber lining works and it was heated with external propane torches after blanking off all openings. Workers heard a whistling noise and ran way. A few moments later the vessel exploded. Heating the vessel externally caused the vessel to over pressurize and rupture. Read the case study in this link.

March 6, 2012

On line leak sealing

Sorry, the previous post on online leak sealing had a bad link....
Recently, I had met a senior colleague of mine called Mr S.Raghavachari after a gap of 20 years. While reminiscing about the "good old days", I remembered that he had written about online leak sealing. I mentioned about my blog and he promptly sent his article on the subject to share with readers.I thank him for sending the article.
Online leak sealing is effective if all hazards are evaluated. There have been numerous accidents during on line leak sealing, mainly due to the mushrooming of fly by night operators. Be careful while choosing your on line leak sealing contractor. Ensure he has the proper technical background and support.
 You can read Mr Raghavachari's article in this link.

March 4, 2012

Deadly explosion in pesticides factory

An explosion has taken place in a pesticide factory in China. A news article mentions that "According to the preliminary investigation, the major substance that caused the blast was guanidine nitrate, a combustion-supporting chemical that can irritate the eyes, skin and upper respiratory system. The specific cause of the accident is still under investigation"
Read about the accident and see photo of the blast zone in this link.

March 2, 2012

Don't make a mockery of a mock drill

The recent unfortunate death of a young woman  volunteer in a mock drill at Bangalore, speaks volumes of the state of emergency preparedness. In many chemical plants, mock drills are conducted by informing everyone about the timing of the drill. What is the purpose of this if you want to test your real emergency preparedness? In 1995 I attended an advanced firefighters and rescue training at Dubai where not only were we made to fight live natural gas fires generated in a natural gas skid mounted mock plant ( we had to isolate the supply of natural gas) but also made to search for victims inside buildings. Smoke bombs were placed inside the buildings to disorient us, along with strobe lights that were flashing ( also to disorient us). The instructors place a lot of emphasis on the safety of the firefighters and rescue team. Recently I read an article about a new training tool for firefighters in this link.
Always be prepared and don't make a mockery of a mock drill.

March 1, 2012

Silo collapse in fertilizer factory

A silo structure collapse in a fertiliser factory has led to injuries to 15 people.The cause of the incident is under investigation. Ensure that all structures (both civil and structural) are inspected and maintained properly. Sometimes, I have observed fertiliser material covering many structures. What you don't see cannot be inspected. Another article Mentions that police have registered criminal cases against the management.
See the video of the collapsed structure in this link
Read the article in this link.

Meetings and Process Safety

Nowadays meetings are the order of the day. Either the plant manager is coming from a meeting or going to one! Net result - plant visits by the plant manager are rare. Process safety needs to be managed by look,listen and feel technique - look at the plant, listen to your shift crew and feel the pulse of what is going on at the plant level! A newspaper report suggests that attending meetings makes one brain dead. Plant Managers - Beware!!!
Read the news article in this link

February 27, 2012

Plane accidents and process safety


"06/23/1967 Mohawk Airlines
BAC-111-204AF Blossburg, Pennsylvania The airplane crashed after an in-flight fire destroyed the pitch control systems. All 34 people aboard were killed. A malfunctioning nonreturn valve allowed hot engine bleed air to flow back through an open air delivery valve, through the APU and into an acoustic blanket lined section of the fuselage. This caused flexible hoses with hydraulic fluid to ignite and lead to an uncontrollable fire".
Beware of check valves!!

"09/06/1971 Pan International
BAC-111 Hasloh, Germany The aircraft collided with a bridge, shearing off both wings, after a double engine failure occurred during takeoff. The water-injection system to cool the engines during takeoff was inadvertently filled with kerosene instead of water".


30 years ago, an operator in the plant I worked filled up antifoam liquid from a drum similar to an oil drum into the hydraulic governor of a large steam turbine. We found out when the governor started misbehaving!!

Source of plane accidents : http://planecrashinfo.com/unusual.htm

February 25, 2012

Fire in Pharma factory

Reports of a fire incident in a Pharma factory mention that hazardous waste stored for incineration caught fire. Are you safely storing hazardous waste as per the norms? Generally, what I have observed in other factories is that the incinerator area, being far away from the plant, sometimes gets a little less attention than it should be getting. Most of the work is also contracted out.Ensure that the contractor employees are trained in the norms of handling, storing and processing hazardous waste.
Read the article about the fire in these links:
Link 1
Link2

February 24, 2012

The importance of emergency stopping

How do you ensure that your emergency stop buttons will work when needed? The emergency stop is the last line of defense and a good article by Robin J Craver mentions the following:
"The nature and operation of the machine must be considered.
· Is it safe to have the emergency stop system cut the power to the machine drives and actuators? This may result in the hazard “free falling” leading to a more dangerous situation.
· Should the system actuate a brake or clamp?
· Would stopping the machine in position result in a worsening of an injury?
· Should the system allow the machine to continue on or reverse to a safe position?"

 Read the article in this link.

February 22, 2012

Process safety and nanotechnology

With nanotechnology, the process safety hazards will change. A whole new nano process safety approach may need to be taken to identify nano hazards. An article mentions the hazards of nano dust. It mentions that "nanomaterial dust could explode due to a spark with only 1/30th the energy needed to ignite sugar dust — the cause of the 2008 Portwentworth, Georgia, explosion that killed 13 people, injured 42 people and destroyed a factory".
Read the article in this link.

February 19, 2012

Fire in refinery

A fire in a major refinery in the US has been reported. Apparently, the fire was due to a flange leak.See the video of the fire in this link.

Pressure vessels and labs / R & D's

I have often seen that personnel in labs and R & D setups do not understand the hazards of a pressure vessel. Many times, pilot plants are built by buying equipment from the second hand market. Not having the specifications / data sheet for the vessel is dangerous. One such fatal incident in a NASA lab highlights the following:
"Vessel at least 33 years old
• Unknown prior service, no nameplate, no drawings
• No pressure or temperature rating information
• Most welds on hold down bolts were cracked before being put into this service

.Vessel design inappropriate for intended service
– Vacuum vessel put into service as a pressure vessel
• Vessel not pressure checked prior to full use
– And no restricted access during initial pressurization
• Critical welds on hold down bolts not inspected after 33+ years of existence
– Were not considered critical for a negative pressure (vacuum) application
• Bolt welds were cracked and cracks exhibited corrosion prior to this use
• Vessel failed (chamber lid separated from chamber body) when all hold down bolt welds broke simultaneously".


Read about the incident in this link.