Apparently the article in the Tucson Citizen that I linked to above has hit its "sell by" date and has been pulled.

The general thrust of the article is that mystery writer Judy Jance has called attention to the possible dangers of sodium azide, a potentially deadly chemical which is used to actuate automobile air bags. The main danger (as far as I know) seems to be environmental. It is a very potent chemical, and when cars with intact air bags are junked, it can get into the environment. But—it also served Jance well in that it provided a convenient method of murder in her most recent mystery novel. Sodium azide is as deadly as cyanide, and although there is probably not all that much danger when you're driving, it does make me a bit nervous to think that it's right there under my nose whenever I'm in an automobile.

When an air bag is actuated, the sodium azide is ignited and within a twentieth of a second it produces large quantities of nitrogen (no danger there; roughly 80% of the earth's atmosphere is nitrogen) which inflates the air bag. It seems to me that there should be all kinds of ways of accomplishing the same thing without using sodium azide. Apart from providing a deadly poison for anyone who might want to get at it, Jance points out that the environmental danger from sodium azide could be essentially eliminated if one of the steps in junking a car was to actuate the air bag.

Here are links to other stories:— Blicky 1 and Blicky 2. And here is more than you could ever possibly want to know about how air bags work: Blicky 3.

Don Firth