5 Myths About Fire-rated and Protective Glass
Here he shares five common misconceptions he sees regularly on the specification and use of fire-rated glass.
1 My building project has sprinklers specified, so I don't need fire-rated glass or other fire-rated interior products.
There's a perception among architects and some code officials that the presence of a sprinkler system waives the need for fire-rated glass. This is an example of a little knowledge becoming dangerous. Past encounters with a particular application that warranted an exemption can easily get misinterpreted into a blanket concept. There is still a strong belief among most within the building industry that passive and active fire protection work hand in hand. This is just one of many examples of a belt-and-suspenders approach to assured performance within standard construction practices.
2 Fire-resistive glazing will satisfy all the requirements of ASTM E 119, so that's all you need to specify.
3 Fire-rated glazing doesn't qualify as safety glass, so I can't use it.
Fire-rated glazing has to comply with the same impact-resistance standards as do other types of glass. Wired glass has lost all of its exemptions from impact standards through code changes adopted as part of IBC 2003 and 2006.
4 If unspecified by the architect, window and door glass decisions can be left up to the contractor or fabricator.
5 ASTM E 05 requires a hose stream test to gauge structural integrity during a fire, so if it passes, I can be assured the products I'm specifying will hold up in firefighting conditions.
No. In fact, the commentary following current National Fire Protection Association test standards that include the hose stream test clearly states that it is not intended to replicate real-world fire-fighting procedures. Spraying water from 20 feet away does not approximate in any way the effects of fire-fighting tactics within the average building corridor. The use of the hose stream is an imperfect attempt to check the structural integrity of building components. It took the place of swinging weights, which was a haphazard means of testing floors and walls. Based on my conversations with fire service professionals, when it comes to fire-rated glazing and fire-fighting in general, the containment of radiant heat within the early stages of a fire is of far greater concern than the structural integrity of structural components. The heat is what causes spontaneous combustion and the rapid spread of fire.