PEPCON Ammonium Perchlorate plant disaster on TV now.

Final word. Welding started fire. Too much AP (8-10 million lbs) stockpiles as a result of the challenger disaster.

Two interesting things I noted:

1. The original investigators tested to see if AP by itself was flammable and if AP in contact with plastic barrels was flammable. They seemed quite excited to see that the latter was quite combustible as it supported their theory.

My commentary: Forensic investigators at a major chem plant explosion do not inherently know that oxidizer + fuel = agressive fire? They had to test to see? And these were their "expert" investigators?!?

1. The investigators tested building very large, very hot fires *under* a series of 500# and 5000# barrels of AP to see if it exploded. Not surprisingly, it did. But it was interesting to hear the commentator say that the investigators were able to achieve a detonation in *most* of the cases.

My commentary: This implies that at least some of the time, it did not explode. If you cannot get reliable explosions by placing sealed barrels of APCP onto the top a 10ft high funeral pyre, large quantities of raw must not be as much of an explosion hazard as the ATFE would like us to believe.

1. A large part of the commentary ws the forensic analysis to see if a buried 15" gas pipeline started the explosion or the pipe was ruptured by the explosion.

My commentary: That implies that a large team of experts started with a signifcant enough doubt that the AP was responsible that they felt the need to explore the gas angle. Granted, exploring all possibilities is their job but one would think that with no other evidence (including live video) to support a pipeline rupture, that would not have been given lesser priority.

Philip

I don't know if back issues are still available, but if you can, check out HPR's "Crash and Burn" issue. It had a very good, detailed analysis of the PEPCON incident written by an expert witness who was involved with the investigation.

pdoolittle wrote:

Is Jerry involved?

>

PLEASE DO NOT FEED THE TROLL....

Was it Chuck Piper? I talked to him at length at BALLS last year about the PEPCON explosion. He said it was a very unusual set of circumstances that allowed the oxidizer to explode, as pure oxidizer by itself is not even flammable. You can heat raw AP with a torch and all it does is glow.

Mike Fisher

If Chuck Piper is also known as Charles J. Piper III, then yes. A couple of excellent articles by him appeared in the July 1998 HPR. "Ammonium Perchlorate: Myth, Mystery, Misconception, and the 'Henderson Syndrome'" and "Ammonium Perchlorate: What Really Happened at Henderson?"

Keep in mind, though, that AP is a molecular fuel/oxidizer system, just like AN and most high explosives. Under the right circumstances, it's quite happy to detonate, with the hydrogens in the ammonium branch interacting with the oxygen in the perchlorate branch.

While we'd all like to *believe* that AP (and by extension APCP) is almost completely innocuous, the chemical reality is rather different.

It used to be believed that AN was rather innocuous--despite the fact that it is a molecular fuel/oxygen system. In fact, they used to break up large agglomerated piles of AN on loading docks using sticks of dynamite. Until one time when the pile detonated. Granted, the pile was likely contaminated, at least on the surface, with some organics. But once it got going, it was game over...

While difficult to ignite, AP can auto combust. In this case, the ammonium is the fuel for the perchlorate oxidizer.

Gary has a video of some AP burning on the Aerotech website.

-JT

Does anyone have the video of the pepcon expolsion posted online somewhere? I've seen it before, it was awesome....

"OdorDestroyer.com" wrote in message news:B8qAd.6132$ snipped-for-privacy@newsread3.news.atl.earthlink.net...

Do you have a link for that?

Thanks,

Niall

I recently recorded History Channel's Modern Marvels: Engineering Disasters

8 which features the PEPCON explosion. They stated that AP heated to 600 degrees will self ignite, and any contaminates would make this much easier. They also said that open storage containers were in the vicinity of open welding. This provided contaminates and heat. Boom!

MAKE A VIDEO CLIP TO PUT ON THE USR WEBSITE. OUR OEM HAD OVER 10,000 LB AP EXPLODE IN THAT INCIDENT :)

Jerry

What did you say? Did you say "OUR OEM HAD OVER 10,000 LB AP EXPLODE IN THAT INCIDENT". I thought AP didnt explode?

Ammonium Perchlorate (AP) is detonable. Ammonium Perchlorate Composite Propellant (APCP), in the formulations that are useful to hobby rockets, is not. There are a few esoteric formulations used by the military that are detonable.

APCP, in anything remotely related to the formulations used by rocketry hobbyists, is not capable of detonation.

Hence the wording in the original Enzi bill, which would have exampted "non-detonable" propellants from regulation as explosives.

- Rick "Pedantry can be fun" Dickinson

So did the owners of Pepcon. (Pacific Engineering & Production Company)

AP under 45 micron in particle size can explode (it is the ONLY AP on the ATF explosives list). Quantities of almost any material above a specific quantity (MEQ) can "explode" (includes the looser terms of the word).

This had HUGE quantities of AP, ignition sources, percussion waves, precursor chemicals including bulk soduim chlorate, and of course finely ground AP for the Titan program and others.

Jerry

I saw a documentry on the disaster, I believe on Discovery, but not sure, anyhow ....the AP was stored in plastic drums and moved about the site in open aluminum containers on wheels.These were quite large and held several hundred pounds. When the fire reached a very high flash point ,the vapors mixed and caused the detonation. A very unusual and rare situation, for a fire to melt and literaly vaporise aluminum, the plastic is understandable. Once the fire got going it created a large draft, sort of a fire storm, the winds increased the temperature even more, like bellows in a blacksmith shop. Do the math......oxidizer + fuel superheated= BOOM

OEM, shmoe e m. Powertech was the manufacturer and you were a member of Powertech.