Chemical Process Safety (PSM/RMP)

A contractor at an upper-tier Seveso plant was cleaning an underground tank so that it could be filled with a different product. The tank was located in an outdoor area comprising 12 horizontal underground multi-compartment tanks, each having an overall capacity of 60 m³ (nominal compartment capacities of 10, 15 and 35 m³) and containing flammable liquids (solvents…...

At around 11:00 p.m., phosgene (COCl2) and chlorobenzene began leaking inside the containment building of a chlorinated chemicals plant. The leak was detected at levels between 13 and 22 ppm by analyzers inside the containment. The analyzers’ control system automatically directed the air inside the containment towards the caustic scrubber. Technicians began looking for the cause of the leak.  While one of…...

The irony in this post is thick with sulfur smoke! SAFTENG Members can read my 2012 article Sulfur sticks and ammonia leaks… are you in compliance when using these leak detection devices? This video shows us what happens when we introduce a lit sulfur stick into an NH3 gas leak.  Imagine someone doing this in a…...

Words still mean something!  There is a reason why OSHA (and EPA) use the word “Management” in the titles of their process safety standards.  Sorry to state the obvious, but the standards are NOT called “process safety managER” for a really good reason.  I have been serious about process safety since 1993 and the one…...

Back in December 2017, I wrote about a change in the Anhydrous Ammonia fertilizer industry that would most likely require the industry to perform a MOC and PSSR. (A new grade of anhydrous ammonia fertilizer means a MOC, PSSR, etc.)  Now that the product has received it’s official approval and has found its way into the…...

Employees #1 and #2 were draining refrigerant oil from anhydrous ammonia refrigeration system oil traps in fruit cold storage warehouse(s). They were working approximately 24 feet above floor level on a mobile scissor lift personnel platform using hand tools including a wrench, a flashlight, and a bucket. The cause of the unexpected ammonia release is…...

On December 26, 1989, Employee #1 was attempting to replace a leaking oil valve on a minus 30-degree freezer when a tank inside the freezer exploded. The company uses anhydrous ammonia to manufacture ice cream. The liquid ice cream mixture (at 50 degrees) is added to the tank. When the liquid ammonia changes to a…...

An oil separator on a two-stage ammonia refrigeration system became overpressurized and exploded, killing Employee #1. While looking for Employee #1 after the accident, Employee #2 fell into a drain. Ammonia that had been uncovered as a result of the explosion had flowed into the drain. Employee #2 was hospitalized…. Membership Required You must be...

At approximately 3:15 pm on May 9, 1986, employees started to charge the number 1 line Carbo-Cooler, using a cylinder containing 150 pounds of anhydrous ammonia at 129 psi (room temperature). Employee #1, in an effort to speed the charging process, was running hot water (132 degrees F) over the ammonia cylinder (to raise the internal…...

A pressure vessel in an ammonia refrigerator system at an ice plant ruptured under pressure of 170 psi. The explosion caused extensive physical damage and released dense clouds of ammonia gas. Employees #1 through 4 died of acute ammonia inhalation…. Membership Required You must be a member to access this content.View Membership LevelsAlready a member?...