What's the chemical in an airbag?

[david c.]

Hey guys,

Can anyone help me identify the recipe for the chemicals in an airbag? I need to find out what is in the airbag of a 2001 Ford Escape.

Thanks if you have any thoughts!

David

[HarryD]

Dave,

What's the beef?

The chemical is Sodium Azide (NaN3). When heated, it forms elemental sodium and Nitrogen gas.

For chemists:
2 NaN3 --> 2 Na (elemental sodium) + 3 N2 (nitrogen gas)

Read more here: http://www.sciam.com/askexpert_question.cfm?articleID=0008ACD8-5AF8-1C72-9EB7809EC588F2D7

[david c.]

Harry,

I am interested in finding out if anyone has ever looked into whether the gas or chemicals in an airbag are problematic for people with respiratory problems, like an asthmatic or someone with pneumonia or the like.

Do you know if it's the same formula in all cars? That would make sense to me, but I have no real experience with air bags. I don't think I've ever owned a car with air bags. My 1990 Miata might have had them but I can't recall.

David

[HarryD]

Dave,

I am not an expert but the stuff it makes is dust and nitrogen. 80% of air is nitrogen so that is not an alergen in my book. Some people can be sensitive to dust. It is possible, but if the article is correct, it is only a handful (130 grams - 1/2 cup) so that is not much either.

[david c.]

Thanks Harry, I'm going to look into the info on that site you listed. I appreciate your expertise and time!

[UconnTim97]

I don't think N2 poses any danger in an open environment

[89911]

I "smell" a suit coming!

[david c.]

Michael,

Not yet, but it just seems to me that someone must have analyzed whether this dust (not so much the nitrogen) is a problem for persons with respiratory illness or weakness.

David

[Doug Zielke]

Originally posted by dave cardone
...someone must have analyzed whether this dust (not so much the nitrogen) is a problem for persons with respiratory illness or weakness.

Yeah. Could be a real problem if they are crashing their cars on a regular basis.

[Moses]

Originally posted by dave cardone
Michael,

Not yet, but it just seems to me that someone must have analyzed whether this dust (not so much the nitrogen) is a problem for persons with respiratory illness or weakness.

David

Not nearly as big a problem as a 60 MPH header into a tree.

This reminds me of the story about the attorney who fell overboard on a chartered fishing trip. He was thrown a "life ring" and pulled safely from the water. Later he sued the charter company because they had not required him to wear a life vest while on board.

[vash]

i swear, i thought the dust was cornstarch. at least it used to be.

[cowtown]

The words "laughed out of court" come to mind...

[HarryD]

Originally posted by dave cardone
Michael,

Not yet, but it just seems to me that someone must have analyzed whether this dust (not so much the nitrogen) is a problem for persons with respiratory illness or weakness.

David

Dave,

I would think the issue is not so much dust but the heat required to do the conversion. This, I think is way, you see soot etc on perole who have released their air bags. Also, the gas and dust should be contained within the bag since otherwise, the bag would not inflate. On the other hand, if someone is playing with the device used to fill the air bag, that is (in my mind) akin to playing with a stick of dyamite and a blasting cap. If you have no business handling these things, you shouldn't be just because you can.

Also, when elemental sodium is exposed to water, it forms caustic soda and Hydrogen gas.

2Na (Sodium) + 2H2O => 2NaOH (caustic soda) + H2 (hydrogen gas)

But as other respondents noted, the action that causes this release is a very violent collision that has (IMHO) risks far in excess of a brief exposure to dust.

You got a lawsuit somewhere?

[Moses]

Originally posted by HarryD
You got a lawsuit somewhere?

Reminds me of a joke.

Q: What happens when a lawyer takes Viagra?

A: He gets taller.

[david c.]

Hey, great joke.

There isn't any lawsuit, honestly. Someone in my office just asked me about it because I'm the de facto car junkie here.

Someone wrote: "The words "laughed out of court" come to mind..." I really don't think it's funny.

Awhile ago, I almost married (gasp) a girl with a severe asthma condition. It was wierd. She was an absolutely knock out beauty, like a 10 on anyone's scale. No viagra was needed.

But certain circumstances and irritants were life threatening to her and it was something that really stayed with me after we parted ways. She had to tip-toe through life with concern for things I'd never thought about. If I (a) had married her and (b) had the misfortune of dealing with an airbag chemical causing her to die, I would have gone ape****, not because I am attorney but because someone should have thought about it ahead of time.

[HarryD]

Dave,

I am very glad that someone you know or are associated with was not serioulsy injured from an airbag.

The fact they use Azide is scary to me only due to the heat and fire associated with it's use. The reason they choose it was due to it's light weight, ling shelf life and speed of reaction once triggered.

Take care.

[HarryD]

So Dave,

Did you help out your friend?

[david c.]

Harry,

Still working on collecting the info. I'd really like to know how to get the specific MSDS for the car.

David

[HarryD]

Originally posted by dave cardone
Harry,

Still working on collecting the info. I'd really like to know how to get the specific MSDS for the car.

David

The MSDS would most likely be obtained from the manufacturere of the air bag or the sodium azide canister.

A google search for --> MSDS "Sodium Azide" <-- turned up lots of hits. JT Baker's MSDS looks like this: http://www.jtbaker.com/msds/englishhtml/s2906.htm.

FWIW, JT Baker is a big chemical supplier and generally I like the quality of their MSDS sheets.

[david c.]

Thanks again Harry!