Plexiglass is not suitable as safety glazing – this is pretty much the only disadvantage of this type of plastic sheet. There are two reasons for this: it is flammable and it is difficult to break Plexiglass. It is not easy to break plexiglass, this requires a lot of strength. It is 30 times more impact-resistant than glass, but once it breaks, a single large fault line is created. Plexiglass is flammable and starts burning at temperatures from 450 ° Celsius so therefore It should not be used as glazing in means of transport or as a shield for heat sources.
Vandalism and fire considerations when purchasing acrylic sheet
Due to its high impact resistance, acrylic is hugely popular as a substitute for glass. But in public spaces, there is another potential risk: vandalism. One form of vandalism, in particular, shows the vulnerable side of Plexiglass, namely its sensitivity to open flames. Just take a look at it in buses, trams and guard booths: how often do you see traces of fire because someone has held a lighter against the glazing? Polycarbonate is often used as glazing in places where this type of damage is a possibility.
Plexiglass is flammable and therefore not suitable for places where high temperatures, open flames or sparks can occur. This is not only the case with fireplaces or heaters but also with many operations in a workshop. Just think of welding, flame soldering, grinding … Sparking is always a possibility. Now acrylic sheet will not immediately burn when exposed to sparks, but sparks will certainly burn in, causing the material to smoulder.
Harmless when burned
Every disadvantage has its corresponding advantage, and with Plexiglass the advantage is that when burned it burns away completely to water vapour and carbon dioxide, completely harmless substances. When burned, it will also hardly form any smoke, the flue gases are completely harmless. Burning acrylic can be extinguished with common extinguishing agents, such as water and foam. Smaller fires, such as flames from burned-in sparks, can normally be blown out like a candle.