The Honeywell complex near the Ascension/Iberville Parish line had an apparent explosion and leak of toxic hydrogen fluoride and chlorine Monday night but local law enforcement lifted highway closures after the all-clear was given about an hour later, authorities said.
Ascension Parish sheriff’s deputies said an explosion or loud bang was reported from the Mississippi River plant off La. 3115 about 8:15 to 8:20 p.m. but Sheriff Bobby Webre said no fire or fireball was reported.
Webre said that while it remains too early to tell, it appeared that the incident was more like a pipe or valve that burst due to high pressure.
Honeywell ordered a shelter in place due to the leak, state regulators said, but preliminary reports from fence-line monitoring did not detect any off-site impacts.
It’s not clear yet how much chemical was released. Those estimates are usually not something that is made public for at least a week to 10 days.
Deputies said there were no injuries.
Webre said the release of the two chemicals resulted in a mist that slowly dissipated.
Hydrogen fluoride, which becomes hydrofluoric acid when mixed with water, is a potent toxic chemical that can be fatal after contact with the skin in high enough concentrations. The chemical can also cause breathing problems, including fluid in the lungs, if inhaled in high enough concentrations.
Low concentration contact with the skin can lead to painful, slow-healing burns, the U.S. Centers for Disease Control and Prevent says.
In October 2021, a Prairieville man and Honeywell employee was killed after a valve failed and leaked hydrofluoric acid on him.
The Geismar plant uses hydrogen fluoride in units that make refrigerants. A Honeywell spokesman could be immediately reached late Monday night by email.
Chlorine is a toxic, heavier-than-air gas that can linger and move along the ground and suffocate people at high enough levels.
Lt. Col. Donald Capello, Ascension sheriff’s chief of criminal operations, said that after the initial report of some kind of explosion or incident, deputies began closing highways under a standard protocol for incidents in the Geismar area.
But deputies closed, for a time, the intersections of La. 3115 and River Road, La. 3115 and La. 30, and La. 30 and La. 73.
Honeywell is located near the Ascension/Iberville parish line in the Geismar/Carville area. The site is in the northeast quadrant of the intersection of River Road and La. 3115.
The main entrance is on La. 3115 in Iberville Parish.
*Original full-text article online at: https://www.nola.com/news/all-clear-given-after-toxic-release-at-honeywell-in-geismar/article_cc79681c-f265-544f-9c9c-4001a1b5975e.html