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How poisionous is sodium azide?

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gbent

Agricultural
Jan 6, 2002
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In a few moments of leisure, I read a new book by J A Jance called Partner in Crime, where the villan used sodium azide as a poison. An internet search turned up a number of alarmist web sites about it's toxicity. What, if any, precautions does one need to take about handling the unfired canisters? What if someone has opened a canister without setting it off? All of my play vehicles are to old to worry about airbags, but some of the early air bag vehicles are getting cheap enough to look at.
 
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I don't know, but I can tell you that when mechanics work on cars at a crash facility (ie they do it all the time) they don't bother with disabling the airbag system. These guys will see a lot more airbags go off than any normal person, so far as I know they don't get sick.

Cheers

Greg Locock
 
I have voiced concerns about 'handling' unfired systems several times in these forums. Admittedly it's much like preventing teen pregnancy by telling them not to have sex.
Be that as it may---at some point we are going to read on page two that some fool has blown his hand off or blinded himself---so be it! Fortunately this is yet to happen but working on these system should be no more dangerous than handling unfired munitions if you are trained and proper safety procedures are followed. This is no longer new technology . MSDS are available as are tech books on 'how too'---READ THEM! Systems are coming on the market for retrofit (should prove entertaining). I have already seen a couple of early cars with Mustang wheel/airbags in functional (?) condition.
My father tought me how to use explosives when I was a child and I have never forgotten his warnings, not that the opportunity to use these 'skills' presents itself often. Read the books, take the classes, excersize proper care (hopefully you still have BOTH thumbs) and just about any dangerous job can be undertaken with safety.
This is another one of those automotive jobs best left to the "professional". At least if he screws up he can collect workmans comp.

Rod
 
Why would you open it anyways? I don't even know if you could get it open without it being set off. When we replace them we blow them off to disarm them and at that point the sodium anzide has burned up and turned into harmless nitrogen. I've worked with unfired airbags there no big deal as long as you don't try to check them with a multimeter :)

On a side note, not all systems use sodium anzide, some systems use other chemicals or pressurized gases such as Argon.

 
Folks:
The information you need is found on a document known as a Materials Safety Data Sheet: there are several of them available for this compound, varying greatly in usefulness depending on their age. A summary follows:

NaN3 is a white, crystalline powder that is toxic and highly reactive.

It's pathways are by inhalation, ingestion and skin absorption.

It's LD50(Lethal Dose-50% of exposed population)is 27mg/kilo, or about .25 grams for a 200 lb person, when ingested. At higher dosages (1 or more grams) death occurs within 40 minutes(this is known from a suicide in Japan). There is no known antidote or effective treatment.

It's LD50 via inhalation or skin absorption is unknown: it is believed to be very fast acting if inhaled.

It's lethal mechanisms are manifold: it demylinatnes nerve tissue, binds with hemoglobin(blocking oxygen transport), and is extremely hypotensive(results in acute lowering of blood pressure)

When dissolved in water, it is odorless, colorless and tasteless.

If exposed to acids, it forms Hydrozoic acid, which is very toxic by inhalation.

If exposed to metals such as copper or lead, it forms highly explosive and unstable compounds(lead azide is used in detonators)

In auto air bags, it occurs as stacked tablets in a metal canister: the driver's side bag typically contains about 50mg and the passenger bag about 200mg.

This is nasty stuff: luckily, I know of no reason for anyone to pry open an unfired canister of this stuff, but if one did, you could do a lot of damage.
 
I used to work at an airbag manufacturer. BIGRED1 gave som e good toxicology data. There are some other bad actors in the ignition train that should be avoided. Because 2 of the actors in the ignition train are very static sensitive, I would suggest leaving them alone.
 
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