FATAL ACCIDENT DURING FILTER CHANGE

 http://wyomingworkforce.org/_docs/osha/accidents/09-14-2016.pdf

Do not be fooled by water wells

 http://wyomingworkforce.org/_docs/osha/accidents/06-05-2018.pdf

Fire inside confined space due to halogen light

On Dec. 17, 2013, the worker was spraying a flammable coating on the inside walls of a large steel tank when a fire was ignited by a portable halogen light. The 37-year-old man was rescued but spent three days in the burn unit at Hospital.

Cal/OSHA cited the company for these and other alleged violations:

• Knowingly using an unauthorized electric lamp while the painter was working in an explosive atmosphere.
• Not having a permit to work in a confined space.
• Not having the proper ventilation or protective equipment for such a hazardous space

Source: CAL Osha

Flammable vapours + ignition = Fire

 On September 9, 2005, Employees #1 and #2 were replacing a sump pump on a premium gasoline pump at a BP Gas station. The pump, powered by a 220 volt line, was in a sump that was used to contain fuel residue. After the installation of the new pump, it was tested and failed to operate. While Employee #1 was checking the pump voltage with a volt/ohm meter, he became distracted and allowed a meter lead to short to ground. The resultant spark ignited fuel vapors in the bottom of the sump and caused a flash fire. Employee #1 sustained first-degree burns to his hands and face. Employee #2 was hospitalized first-degree burns to his face. 

Source: osha.gov

Lessons Learned from a Hydrogen Explosion

Lessons Learned from a Hydrogen Explosion: On January 8, 2007, a hydrogen explosion at the Muskingum River Power Plant’s 585-MW coal-fired supercritical Unit 5 caused one fatality, injuries to 10 other people, and significant damage to several buildings. The explosion occurred during a routine delivery of hydrogen when a hydrogen relief device failed, which allowed the contents of the hydrogen tank to escape and be ignited by an unknown source. This article covers the findings of the incident investigation and the actions the plant has taken to prevent a reoccurrence.

Small bore tubing incident

A gas leak occurred at a compressor station when small bore pipework fractured. The incident resulted in a small natural gas release that was successfully resolved without harm, although the licensee identified the potential for the situation to have escalated if it was not for the careful inspection prior to works being undertaken.The small bore pipe that failed was a low point in the drain system located in a pit that was not readily accessible.The root cause was identified as the small bore pipe that failed had not been designed to handle vibration resulting from high gas flows and decreased suction pressures. The small bore pipe’s limited accessibility resulted in it being missed on previous site reviews specifically undertaken to identify potential points of failure due to vibrations.

Source:https://www.dmp.wa.gov.au

HYDROGEN FIRED BOILER EXPLOSION

Bypassing of safety interlocks during start up of boilers have caused many explosions around the World, killing many people. I had investigated one incident where a hydrogen fired boiler was being commissioned and the trips were bypassed as they were causing some problem. The boiler exploded and the operator was killed. Read about another hydrogen fired boiler explosion in this link:

 https://www.dmp.wa.gov.au/Documents/Safety/PGS_SIR_01-2016.pdf

Explosion in molten sulphur tank

Molten sulphur tanks are often not given the importance they deserve. because of the nature of the product, they are dangerous and have to be handled with precautions. This safety alert explains the case of an explosion in an molten sulphur tank. Ensure the learnings are shared. Read the safety alert in this link:

https://epsc.be/epsc_media/Learning+Sheets/2019/19_06+EPSC+Learning+Sheet+_+H2S+explosion-p-660.pdf

Inspection frequencies and OSHA

The most commonly cited equipment for non-compliant inspection frequencies (of any type, not only thickness measurements) have been piping circuits followed by pressure vessels, relief devices, and monitoring alarms. As part of the inspection program, an appropriate inspection frequency must be established for equipment in order to determine whether pipe/vessel thickness is decreasing as expected. API 570 identifies three classes of piping services and recommends a thickness measurement inspection frequency based on the class. For example, Class 1 includes:

• Flammable, 
• Pressurized services that may rapidly vaporize and explode upon release,
• Hydrogen sulfide, 
• Anhydrous hydrogen chloride, 
• Hydrofluoric acid 
• Piping over water of public throughways, and
• Flammable services operating above their auto-ignition temperature.

As discussed in API 570, Class 1 requires a thickness measurement inspection frequency of at least every five years. Classes 2 and 3 require a thickness measurement frequency of at least every 10 years. The inspection interval for specific piping is established by the inspector or piping engineer in accordance with the owner/user’s quality assurance system, but not to exceed the limits set by API 570

Source:Osha.gov

OSHA ASSET INTEGRITY OBSERVATIONS

Examples of equipment cited for violations of the PSM MI requirements that OSHA found during NEP inspections include:

• A broken gate valve caused a level gauge to not work properly, which rendered visual verification of liquid level for the vessel ineffective. This deficiency went uncorrected.
• The installation of an engineered clamp failed to correct a deficient piece of process piping, which was a 90-degree elbow that was outside acceptable limits. The employer continued to use the leaking 90-degree elbow as part of a piping circuit that conveyed waste hydrogen sulfide gas.
• Hydrogen sulfide monitors were not inspected and tested on a regular basis to correct deficiencies in alarms that were outside acceptable limits due to bad sensors, loose wiring, or monitors that needed to be replaced. Work orders were not managed by a tracking system to ensure that deficiencies were fixed in a timely manner. Some work orders marked “fix today” or “ASAP” were not fixed for a week or longer.
• Six relief systems in an alkylation unit were incorrectly sized and were not corrected in a timely manner when the deficiencies were reported. No Management of Change (MOC) was performed to justify the decision to delay replacing the deficient systems.
• Grounding cables were removed from equipment, such as a heat exchanger and pump motors, but were not replaced. 
• Excessive vibration was observed on motors with visible movement of structural steel decking and supports. Also, two 1” pipes and one 4” pipe containing flammable liquid were not adequately supported

Source: Osha.gov

ASSET INTEGRITY ISSUES

Failure to correct equipment deficiencies that are outside acceptable limits39 is one of the leading causes of PSM non-compliance in the petroleum refinery sector. Non-compliance for equipment deficiencies broke down into four major groups:

1. Lack of proper maintenance or repair, 38. 29 CFR 1910.119(j)(1)(i)-(vi)39. 29 CFR 1910.119(j)(5)OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION18
2. Inappropriate installation (such as inappropriate sizing),
3. Missing protective system (such as not including relief devices), and
4. Insufficient structural support.

Equipment most commonly cited for deficiencies were relief devices, followed by piping circuits, pressure vessels, and alarm systems.

Source:Osha.gov

 

Dust collector system explosion

Employee #1 was feeding 400 lb of granular polyalphamethyl styrene (CAS 25014-31-7) through a Mikropal #3 micropulverizer (equipped with a .032 in. screen) into a Mikropal Mikro-Pulsaire dry dust collector. The Mikro-Pulsaire unit has a continuously self-cleaning bag filter located inside the building and had no provision for explosion relief or venting. Apparently a piece of metal between 1 and 2 in. got past the magnet in the micropulverizer, ignited the dust in the system, and caused a fire and explosion that blew open the access door to the dust collector. Employee #1 was standing about 10 ft from the door and sustained second- and third degree-burns on his hands and face. 

Source:Osha.gov

NECESSITY OF REMOTELY OPERATED SHUT OFF VALVES

Thousands of gallons of a highly flammable hazardous chemical spilled for nearly 30 minutes before catching fire at the Intercontinental Terminals Co. tank farm in Deer Park, but the facility did not have a remote emergency shutoff valve nor an alarm to alert workers, according to the U.S. Chemical Safety Board. Source: CSB

Have you studied your system to check the necessity of remotely operated shut off valves?

EXCESS FLOW VALVES MAY NOT WORK PROPERLY

More than 35,000 gallons of propane were released when the discharge hose on an LPG transport truck separated from its hose coupling at the delivery end of the hose, and none of the safety systems on either the truck or the receipt tank worked as intended to stop the release. The DOT determined that emergency systems such as EFVs do not always function properly when a pump is used to unload the protected vessel. If a release occurs downstream of the pump and the EFV activation point is greater than the pump capacity, the pump will function as a regulator limiting the flow to below that required to close the EFV. Courtesy EPA.gov

INCIDENT DUE TO FAILURE OF TWO EFV'S

A methyl mercaptan release occurred when a pipe attached to a fitting on the unloading line of a railroad tank car fractured and separated. Fire damage to cargo transfer hoses on an adjacent tank car also resulted in the release of chlorine gas. Neither of the two EFVs closed to control the release. Three plant employees were killed in the resulting explosion and several employees were injured. Approximately 2,000 local residents were evacuated from their homes for 10 hours. Failure of the EFVs to close contributed to the severity of the incident. The NTSB determined that the facility placed undue reliance on the tank car EFV to close in the event of a leak from the transfer line.Courtesy NTSB.gov

INCIDENT DUE TO FAILURE OF ESV

A chlorine railcar transfer hose ruptured, releasing 48,000 pounds of chlorine. Hundreds of residents were evacuated or sheltered-in-place, and sixty-three local residents sought medical evaluation; three were admitted to the hospital. The chlorine also damaged tree leaves and vegetation around the facility. The CSB determined that an excess flow valve internal to the chlorine railcar did not close, contributing to the severity of the event. As a result of such chlorine releases, the CSB has issued a recommendation to the Department of Transportation (DOT) to expand the scope of DOT regulatory coverage to include chlorine railcar unloading operations and ensure the regulations specifically require remotely operated emergency isolation devices that will quickly isolate a leak in any of the flexible hoses (or piping components) used to unload a chlorine railcar.Courtesy EPA

AUTO IGNITION INCIDENT

An oil spill occurred due to a failure of a block valve to seal properly during maintenance of a pump strainer in the visbreaker unit at a plant in Wickland, Aruba, Dutch Antilles in 2001. The oil auto-ignited and the ensuing fire spread and destroyed the visbreaker and damaged adjacent equipment. Estimated loss was USD 250 million current value. (Marsh)

REMOTE OPERATED ISOLATION VALVES

The Center for Chemical Process Safety has given some good guidelines for remote operated shut off valves. In Many incidents, the consequences are magnified as there was no remote operated shut off valve provided. In many fires and toxic gas releases, the manual isolation valves get engulfed and make it impossible to enter the area to operate the valves. Read the guidelines in this link:

https://www.aiche.org/ccps/remote-isolation-and-shut

Incident of failure of SDV

A recent incident involving the failure of a shut down valve (SDV), and the subsequent failure of two pressure safety valves (PSV), has highlighted issues associated with the selection of SDVs and the need for regular maintenance and testing of SDVs and PSVs.The failure occurred after an electrical supply fault caused an emergency shutdown of a gas processing plant. Upon subsequent start up of the plant and one of the plant’s compressors, an SDV passed on closure allowing the gas pressure to build up in a crossover header between high pressure and low pressure pipework systems. Another compressor was then started further increasing the pressure. Two PSVs in the gas line failed to operate at their set pressure and the pressure continued to rise until a rupture disk relieved to flare.
Courtesy: NOPSA
Read the safety alert in this link

Corrosion in Water Based Fire Sprinkler Systems

Good article!
https://www.facilitiesnet.com/firesafety/article/The-Hidden-Threat-of-Corrosion-in-WaterBased-Fire-Sprinkler-Systems--18984