If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.


Industrial Safety

US Chemical Safety Board praises Airgas for its response to 2016 fatality

Agency also provides details on oil field deaths of husband and wife

by Jeff Johnson, special to C&EN
July 30, 2020 | A version of this story appeared in Volume 98, Issue 30


Photo of industrial scaffolding on the left and a row of damaged storage tanks on the right.
Credit: US Chemical Safety Board
A 2016 explosion of a nitrous oxide trailer truck killed one employee at an Airgas facility in Florida.

The US Chemical Safety and Hazard Investigation Board (CSB) issued two significant reports in late July. One praises voluntary actions of Airgas after a deadly incident at a nitrous oxide facility. The second is a factual update to the ongoing investigation of an incident at an Aghorn Operating facility in Texas in which a worker and his wife died from exposure to toxic hydrogen sulfide gas.

The CSB is an independent, nonregulatory federal agency that investigates chemical accidents.

In a Safety Spotlight report, the CSB lauds Airgas, now a subsidiary of Air Liquide, for rapidly developing and implementing a robust process safety management program (PSM) in response to an explosion in 2016 that killed one worker.

CSB stresses that the effort was voluntary, as nitrous oxide handlers are not required by US federal law to develop a PSM program. The incident occurred during the loading of a trailer truck at an Airgas facility in Cantonment, Florida. In the transfer, a pump heated the nitrous oxide above its safe operating limits, causing decomposition and the explosion.

According to the CSB, after the incident, the company began to review its safety programs for its nitrous oxide production facilities, trucking fleet, and cylinder-filling operations. The review resulted in several reforms, such as better audit practices and inherently safer designs.

The CSB issued its investigation report and recommendations in 2017. In the Safety Spotlight, the agency notes that by 2019 Airgas had reengineered its approach to managing process safety in its nitrous oxide business.

“Taking proactive, effective action, similar to what Airgas did following this incident, is the hallmark of driving chemical safety change,” says CSB chairperson Katherine Lemos.

In a statement, Airgas notes that it shut down the Florida facility but uses the PSM program it developed at its nitrous oxide facilities that are currently operating.

“We appreciate the collaboration with the Chemical Safety Board throughout this investigation,” Airgas adds.

The board’s investigation found that explosions had occurred at US nitrous oxide facilities an average of once every 4 years since 2001. Since 1987, such incidents have killed 6 workers and injured 21. Half were caused by an overheated pump, like the explosion at Cantonment.

The Aghorn accident occurred in 2019 at an oil-field station where water used to extract oil and gas is recycled and returned to further enhance oil and gas production. A pump failure caused the release of water containing hydrogen sulfide, the CSB says in its update. An automatic warning system notified an Aghorn employee of a problem, and he drove to the site to investigate.

When he failed to return home 3 hours later, his wife went to the site with their children. Emergency responders later rescued the children from their car and found the parents’ bodies inside the pump house.



This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.