Reading back over my post I'm not sure I fully expressed my point.

Like Patrick, I don't have any great problem if a safety device which makes sense is made mandatory. The problem is when a safety device that operates under a commercial protection which makes it immune from competition is made mandatory.

To take the automobile example, in Europe fitting seat belts in cars was made mandatory over thirty years ago. The laws that made them mandatory defined the performance levels that those seat belts must meet but they didn't say "And you can only buy them from Bob's seat belt company".

We have a requirement under Health and Safety legislation that says that the blades on machines like circular saws must come to rest wirhin seconds of being switched off. The logic is that a near silent running blade with 90% of the energy of a noisy running blade is more dangerous than a noisy one with 100% of the energy. This is usually achieved with DC electric braking. The law that requires it doen't say how it has to be achieved or from whom the technology must be purchased. It makes sense and competition exists to drive down the price. You can now retrofit this technology to an old saw for about thirty pounds ($50ish)