Why not patent an alternative that is difficult to set off accidentally and then sell it for a fortune? Breaking the glass is not dangerous just use your elbow or take off your shoe and use it. In a genuine alarm you wouldn't think twice about a poosible cut.
Correct. Breaking the 'glass' was deemed dangerous and quite difficult if you dont have an item to do it with. That is why BS5839 (The fire alarm british standard) changed the requirements to make sure the 'glass' was easily breakable but not too easy. I believe that the 'glass' is now plastic sandwiched inbetween two pieces of laminate. The legend 'Break Glass in Case of Fire' is still used because I suppose it would be difficult to print 'Break Plastic Sandwiched between 2 bonded sheets in case of fire' on a small piece of 'glass'
It is NOT dangerous,as most Fire Alarm glass merely shatters(like a car windscreen) into thousands of tiny pieces.The glass also serves another purpose,it stops idiots from setting off the alarm"for fun"!
The glass in the alarm point is not glass, it is plastic that has a hairline crack down the middle which when pressed with the thumb breaks in two to press the button behind it.
No edges are exposed as the plastic is sealed over with a sticker film.