August 18, 2018

Cross sensitivity of detectors

During an examination of a liquefied natural gas (LNG) carrier whose cargo tanks contained ethylene vapors, CO (Carbon Monoxide) gas alarms were received which were traced to an eight-inch crack on a cargo vapor line.
It was noted that the molecular weight of Ethylene (28 g/mol) was identical to the molecular weight of CO, which accounted for the CO PPM readings.  Coast Guard personnel contacted the manufacturer who confirmed that gases such as methane, propane, ethylene and mercaptan, could actuate the CO sensor without ever coming into the range of the LEL limits.

As a result of these events the Coast Guard “strongly reminds all surveyors, marine inspectors, port state control examiners, and any other persons utilizing portable gas monitors and detectors while working onboard on Liquefied Gas Carriers to remain acutely aware that the ethylene gas vapors can exhibit cross-sensitivity.  This issue is not limited to the monitors that the Coast Guard uses but also those made by other manufacturers.  Everyone using a monitor must be aware that if the CO alarm goes off it may be an indication of dangerous gases or chemical vapors and not the presence of CO.  When the alarm sounds users must take corrective action to minimize exposure risks.”
Courtesy: USCG

August 5, 2018

Level gauge and Bromine Transportation incident

Mixed acid charging in the reactor was in progress. Level gauge of mixed acid measuring vessel broke and mixed acid splashed on the body of two employees, injuring them seriously. Root Causes: Inadequate preventive maintenance, Employees not aware about potential hazard involved in the operation.

Transportation of Bromine carried out in glass bottle having 3 Kgs capacity in wooden box by goods vehicle. During transportation few bottles broken & started leaking. Due to leakage near by area affected with bromine gas. People around the area were affected due to inhalation. Root Causes: Inadequate packing of bromine bottle. Untrained driver.

Courtesy: A.G.Shingore, National Safety Council

July 24, 2018

Loss of Primary Containment (LOPC)

Loss of Primary Containment (LOPC): An unplanned or uncontrolled release of material from primary containment, including non-toxic and non-flammable materials (e.g., steam, hot condensate, nitrogen, compressed CO2 or compressed air).

Source: CCPS Glossary

July 19, 2018

July 12, 2018

Lessons learnt from a refinery fire

  1. A fire started while draining naphtha from a pipeline that ran through a pump house at the refinery.
  2. Investigations revealed that there were three main lapses that led to the fire:

    (a) The refinery had allowed its contractors to drain naphtha from the pipeline by allowing the naphtha to flow out from two open valves and an open flange joint of the pipeline into trays. This open system of de-oiling allowed naphtha vapour to escape into the atmosphere resulting in an accumulation of flammable vapour, which would in turn pose a danger of ignition.

    (b) The refinery had allowed the use of a plastic tray, which was a non-conductive container, as a receptacle for collection of naphtha. The free fall of naphtha onto the plastic tray would allow accumulation of static charges as a result of the friction caused between them. When the accumulated static charges come into contact with any good conductor, they are instantaneously transferred to the conductor. A spark could be caused as a result of the sudden surge of energy during the transfer, which could be sufficient to ignite the naphtha vapour which is within flammable range in the atmosphere.

    (c) The refinery failed to deploy portable gas monitors sufficiently close to the open de-oiling area to give the warning when the build-up of the flammable vapour reached an undesirable level. 
Source: Ministry of Manpower, Singapore

July 8, 2018

First responders practice with large-scale simulation

First responders practice with large-scale simulation: FRANKLIN CO. -- First responders from across southern Illinois were running drills to prepare for emergency situations that could occur in our communities.  Dozens of fire trucks, ambulances, and ...

July 4, 2018

Work permit incidents

  1. Installation of new Sulfuric acid tank was going on. Two employees were welding on top of the tank. Suddenly the neighboring acid tank exploded. Two persons died. Root Causes were nascent hydrogen caught fire and Hot work was going one very near to acid filled tank.
  2. Two workers were doing maintenance work inside the kettle. Personnel from production started charging CO in the same kettle, assuming that it is empty & ready for charging next batch. Due to inhalation of carbon monoxide two workers died in the kettle.Root causes: Ineffectiveness of work permit system .

Courtesy: A.G.Shingore, National Safety Council

June 28, 2018

Integrity Manuals: The Most Significant Factor in Avoiding Asset Failure

Integrity Manuals: The Most Significant Factor in Avoiding Asset Failure: This special report, authored by Richard Fish, Asset Integrity Specialist, demonstrates the importance of integrity manuals when it comes to combating asset corrosion.

June 24, 2018

June 22, 2018

Drum explosions - beware - it happens too often

 Recently a company experienced an incident when a welder was cutting scrap beams in the scrap yard. There was an empty drum in the yard and he wanted to cut open the drum. The moment he pierced through the drum with his cutting torch, the drum exploded and injured him. Luckily it was not fatal.
I have been writing about how you should treat empty, but not decontaminated chemical/oil drums as potential bombs. Read my earlier posts here:

Read a safety alert about drums in this link

June 2, 2018

Static electricty incidents

  1. Solvent unloading from tanker to drums having 200 lits capacity was in progress. 50% of solvent unloaded in HDPE drums. Fire took place near tanker. Solvent storage godown also caught fire. One fatality & nine injured.Root Causes: Static charge generated during unloading solvent from tanker to drum, No proper earthing & bonding arrangement while unloading solvent from tanker to drum to neutralize the static charge, Lack of awareness training. 
  2.  Charging of solid material from HDPE bags to kettle was going on. Fire took place due to static charge resulting in one fatality and three injured. Root Causes: Earthing & bonding was not adequately provided to neutralize the static charge generated. Potential hazard involved in the process was not captured properly by using hazard identification techniques like HAZOP study. 
  Courtesy: A.G.Shingore, National Safety Council