11 October 2002: Children or small people could inadvertantly fool so-called ‘smart’ airbags to the point that the bags become killers, according to a number of airbag manufacturers.

The bags are supposed to turn off and not deploy if the passenger is a young child. But infants and children in child seats can be mistaken for adults because of the weight of the child seats or extra tension in the safety belts, according to DaimlerChrysler.

And small adults who recline, prop legs on the dashboard or fold a leg underneath themselves can take enough weight off seats to be mistaken for children. Humidity and water on a seat can also cause malfunctions.

Airbag supplier Siemens says it doesn't have any system that's foolproof and doubts whether anyone else does.

Ford Motors safety experts say that Ford has lost some confidence in the systems' reliability.

Conventional air bags are considered to be 99.99% reliable, according to Toyota, which says the smart systems aren't anywhere near that.

But the US transport safety agency NHTSA has refused to halt a mandatory phase-in of smart bags, due to begin next September in the US. Instead, it will remind motorists to seat children in back and explain how small adults should sit to avoid fooling smart bags.