Thanks ladies, it sounds like I may be worrying for naught. Phoenix isn't even born yet and I'm anxious for his/her safety. I spoke to a nice guy at the Road Safety Authority and he is going to get back to me if he can find out any further information. I'm an engineer by training and the whole system just didn't sit right with me but perhaps I'm missing a whole heap of factors some of which you have raised.

Off to do my Calm Birth breathing
xx