From: "Wright, Mike" <mwright**At_Symbol_Here**USW.ORG>
Subject: Re: [DCHAS-L] PEPCON article from Chemical Safety headlines
Date: Fri, 4 May 2018 16:24:11 +0000
Reply-To: ACS Division of Chemical Health and Safety <DCHAS-L**At_Symbol_Here**PRINCETON.EDU>
Message-ID: 673A00C44C25834BA3198AADFC1EB7AE0100396E7F**At_Symbol_Here**PIT-MAIL01.uswa-us.local

My union represented the PEPCON workers. Two of us flew out on the next flight to Las Vegas. Initial reports were that as many as a hundred workers were missing and feared killed. When we changed planes in Chicago, the reports were that about 30 were "confirmed" dead. In Las Vegas we got a car, talked our way past the authorities, and drove into Henderson to the local union office. There we learned it was two. I think we both burst into tears - grief for the two; relief for the 30.


The material was oxidizer - ammonium perchlorate - not fuel. But at high temperature it explosively recombines. For years the company had allowed it to permeate asphalt pads and roadways, creating a severe fire hazard. My co-investigator had visited the plant a year before, and had written a scathing report, but there was no PSM standard then, and neither Nevada OSHA nor the local authorities took it seriously.


When the fire started it quickly knocked out the fire suppression system.  At that point the end was inevitable. The workers evacuated the plant and got everybody out of the building next door - a marshmallow factory. The two who remained were the plant manager, who I guess thought he was honor-bound to stay, and the company comptroller, who worked in the on-site corporate headquarters, was in a wheelchair, and was overlooked by the other officials and staff. Most of the ammonium perchlorate was stored in aluminum tote bins on asphalt pads which burned hotly due to the embedded oxidizer. Those bins are what you see exploding in the video.


I assigned two people to the investigation, who spent several months in Henderson. We used the resulting accident report to lobby OSHA for a PSM standard, and when that failed, we used it to lobby Congress, which mandated the OSHA standard and the EPA RMP program in the 1990 Clean Air Act Amendments. I'd like to think the report had a small part to play in that.


Mike Wright


Michael J. Wright

Director of Health, Safety and Environment

United Steelworkers


412-562-2580 office

412-370-0105 cell


"My friends, love is better than anger. Hope is better than fear. Optimism is better than despair. So let us be loving, hopeful and optimistic. And we'll change the world."

                                                                                                                                                                                         Jack Layton





From: ACS Division of Chemical Health and Safety [mailto:DCHAS-L**At_Symbol_Here**PRINCETON.EDU] On Behalf Of ILPI Support
Sent: Friday, May 04, 2018 8:08 AM
Subject: [DCHAS-L] PEPCON article from Chemical Safety headlines


A colleague of mine was driving past the plant shortly after the fire broke out.  He was not from the area and he thought to himself that something unusual was clearly going on there.  Obviously, he couldn't assist and didn't stick around to gawk.  He drove on a few miles to his destination in Henderson several miles away. He got out of the car and was staring at the fire when the blast wave rolled into town.  He reported that it "knocked me flat on my ass".  Dang impressive and what a near miss for him!


Video for those who have never seen it:   Long one here:


Rob Toreki



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Tags: us_NV, industrial, follow-up, environmental

Thirty years ago on May 4, 1988, the Las Vegas valley was rocked by three massive explosions. A fire that started inside a building at Pacific Engineering and Production Corporation (PEPCO) in Henderson resulted in 3 explosions.

Here is a quick list of interesting facts about the incident:

1. PEPCON produced ammonium perchlorate, which is a chemical found in solid rocket fuel.
2. Because of the Challenger explosion in January 1986, there was a large amount of ammonium pechlorate at the plant at the time.
3. It was the largest domestic, non-nuclear explosion in recorded history at that time, according to NASA.
4. The explosions coule be felt 10 miles away. The two biggest blasts measured 3.0 and 3.5 on the Richter scale at observatories in California and Colorado.


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