Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site ssc-vax.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!gamma!epsilon!zeta!sabre!petrus!bellcore!decvax!tektronix!uw-beaver!ssc-vax!eder
From: eder@ssc-vax.UUCP (Dani Eder)
Newsgroups: net.columbia
Subject: Re: Deadly green canister?
Message-ID: <541@ssc-vax.UUCP>
Date: Tue, 4-Feb-86 21:40:41 EST
Article-I.D.: ssc-vax.541
Posted: Tue Feb  4 21:40:41 1986
Date-Received: Fri, 7-Feb-86 20:41:51 EST
References: <8632@ucla-cs.ARPA> <795@hou2g.UUCP>
Organization: Boeing Aerospace Co., Seattle, WA
Lines: 31

> 
> A few thoughts have been bugging me ever since I first heard of this
> "small green canister": 1) the obvious, why is it so deadly, and 2)
> if so deadly, then isn't it also safe to assume that it would be
> contaminating a very large part of the ocean?
> 
From the "STS Payload Safety Guidelines Handbook" JSC 11123, July 1976
Table 3.12-II Flammability and Toxicity Properties of Propellants:

Hydrazine:  Flammable up to 100% vapor concentration, Flammability limits
at 100 deg C 4.7-100% by volume in air.  Toxic, burns tissues, allowable
concentration 1 part per million (PPM).

Monomethylhydrazine: Flammable 2.5-98% by volume in air @ 1 atmosphere.
Toxic, allowable concentration 0.5 PPM.

Nitrogen Tetroxide: Nonflammable but supports combustion. Toxic, 
corrosive, burns skin and eyes.  Allowable concentration 2.5 PPM.

Since the tanks used to store these fluids are fairly rugged, and at least
one large section of the Challenger survived to land in the ocean, it is
quite possible that at least one of these tanks survived.  Under normal
landing conditions, ground crews wear protective suits with independant
air supplies while they check for leaks of these materials just after
the shuttle lands.  If you see anything that looks like a tank (cylindrical
or spherical) washed up on a Florida beach, particularly if it is wrapped
with yellow fibers (Kevlar), get away FAST and call NASA, the Coast Guard,
or whatever.  

Dani Eder/Advanced Space Transportation/Boeing/ssc-vax!eder
ZZ