RISK BASED PSM PROCESS SAFETY MANAGEMENT INDIA CONSULTANT INCIDENT INVESTIGATION HAZOP TRAINING ROOT CAUSE ANALYSIS AND LESSONS FROM INCIDENTS
October 28, 2021
Employee Location Monitoring in a Post-Pandemic World
October 24, 2021
Improving Asset Inspections with Drones and AI
October 20, 2021
Flame-Resistant Clothing: Everything You Need to Know
October 16, 2021
Protecting Battery Energy Storage Systems from Fire and Explosion Hazards
October 12, 2021
Preventing and Mitigating Oil Fires in Power Plants
October 8, 2021
Does your safety observation system create victims, villains?
October 4, 2021
FATALITY DUE TO EXPLOSION IN NITRIC ACID TANK
A small steel process tank was filled with multiple metal baskets of tantalum capacitors cooked overnight in hot nitric acid. The hot nitric acid was used to remove some of the epoxy resin encapsulant from a tantalum anode. The nitric acid was drained each morning after the capacitors were cooked. The baskets of cooked capacitors were removed and rinsed in water. Mostly tantalum anodes remained. Employee #1 was killed and five other employees were seriously injured as a residue, containing picric acid, exploded, when Employee #1 placed a basket back into the drained tank, presumably to remove more encapsulant. Picric acid (trinitrophenol), and possibly other unstable nitrated compounds, formed in a nitration reaction between nitric acid and the bisphenol moiety of the epoxy resin. These nitrated compounds precipitated out of the nitric acid solution. Over time, as the spent nitric acid was drained from the tank after each batch, the precipitated nitrated compounds would accumulate on the inside surface of the tank. The spent nitric acid was typically used for multiple batches further concentrating unstable nitrated compounds on the tank's surface. Placement of the basket was likely the source of ignition. The explosion was estimated to be of a magnitude similar to an explosion involving more than 5 pounds of trinitrotoluene. The five seriously injured employees were treated for burns and bruises at a local hospital.
Source:OSHA.gov