I think it's definitely useful and smart to have something. One of our drivers who rolled 2 1/2 times last weekend and doesn't have one, said his head banged off everything and anything in the car. He'd been considering one but had put it off...
On the other hand, the week before that incident I had to help a driver out of a burning car, and he had a Hans device on. It didn't impede the rescue as it was an open wheel car, but I can imagine in a closed wheel car it might make it a little more difficult to get the driver out in a hurry if you have to.
We've seen a couple of different types, and more frequently too, over the last couple of years. I would just say for all of those racing to make sure that the volunteers know how to get you out of your device if they have to in an emergency situation. Every second might count!
Nial- Sorry to hear about the accident. At the end of the day, we all know that racing is a dangerous hobby, all it takes is one freak thing to happen and all the safety gear in the world isn't enough.
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