We are currently design a 400 room hotel. Due to fire regulation the fire brigade requires access to each room through the facade. The glass will be silk-screened and therefore tempered. The local fire brigade does not accept breaking tempered glass in a rescue situation. We are looking for documentation on how tempered glass may be broken most efficiently.
There is frequently a misconception that tempered glass is unbreakable. This is not true. Due to high tension caused in the tempering process (the glass is heated and then rapidly cooled) the tempered glass is most resistant than regular one but not unbreakable. The most efficient way is to puncture it with a sharp object anywhere on the surface. The tension forces will cause the glass glass explode it into a million small pieces.
One or two clicks with an automatic centre punch is usually enough to shatter tempered glass up to 10mm thick. Above this thickness, you may need to click the punch a few more times in the same spot. The pointed end of a firemans axe will go through in one!
"silk screened therefore tempered" Does not compute for me. Do you believe that it is neccessary to have tempered glass for the silk screen process to work? That is not a valid assumption. We can screen print on almost any substrate. Do you presume that the process of silk screening will somehow cause the glass to become tempered? A valid assumption only if the printer uses thermoset ink which will require the application of heat for the ink to cure. There is no reason to use thermoset. Numerous other inks and process methods will yield a perfectly satisfactory result. Also glass may be etched with the screen process but the etching will not temper the glass.
Y dont you design your facade with openable windows....they are so common !
You should not have any problem with ur fire dept also !
regards
Saileshac
saileshac@gmail.com