If the airbag doesn't go off when the wheels aren't moving, then when somebody drives into the stationary traffic at 40 mph, you're hosed. Exactly that happened to both my cousin, in Maryland, and a lecturer I had at college. In the
lecturers case, it was a truck that hit his car as he waited at lights. Fortunately for him he drove a Volvo! Anyhow, I'm sure they work when stationary, and if not,...