Wednesday 20th September, 2017
For most of us over a certain age, when we think of fire glass, the image that immediately springs to mind is the wired glass panels in big heavy fire doors that used to be in schools up and down the country.
That’s because, up until relatively recently, the only option for fire glass in doors was exactly that – wired glass that could only be used in doors in relatively small panels because of the risk it posed on impact.
Of course, fire glass has evolved massively since then, thanks to huge advances in glazing technology over the past few years.
But there are still a number of commonly-held misconceptions about fire-rated glass. Read on, and we’ll bust those myths…
This is a myth that has somehow gained credence from a small minority of fire sprinkler manufacturers suggesting that fire-rated glass is not needed where sprinkler systems are in place.
They claim that as the sprinklers activate as soon as a fire starts, the glass will be doused in water and will therefore stay cool enough to remain in place. So therefore non-fire-rated glass such as toughened or heat strengthened glass should be adequate protection.
Of course, the reality is very different. Active fire protection, such as a sprinkler system, is not infallible. Without the passive fire protection offered by fire-rated glass, any malfunction in a sprinkler system could prove catastrophic.
Traditional wired glass is not a true safety glass because it doesn’t meet impact requirements. However, safety wired glass has now been developed that incorporates a safety film, which holds the glass in place should it break. As long as the safety film is certified to be fire resistant and is afixed to the wired glass by competent professionals, there is no reason for it not to be used in glass fire doors.
Toughened glass can withstand temperature changes up to around 260°C, so is considerably more resistant to thermal breakage than standard annealed glass, which will shatter at around 120°C. However, fire-rated glass is able to withstand temperatures of more than 870°C.
Bearing in mind the average property fire will reach up to around 600°C, it’s clear the only glass suitable for fire-resistant barriers is fire-rated glass.
Toughened fire glass is now available, which can withstand higher temperatures, but it shatters on contact with cold water so is unable to pass the hose stream test. This means toughened fire glass is somewhat limited in its applications, and is available only with an integrity rating of 20 minutes and no insulation rating.
We’re well past the days where wired glass was the only fire-rated glass available. Nowadays, we frequently use intumescent laminated glass and ceramic glass, which both have high impact ratings and are considered safety glass. This makes them ideal for use in fire doors and sidelights, where impact safety is a concern.
Thanks to advancements of intumescent laminated glass, this myth is firmly put to bed!
Leading glass manufacturers have now developed products such as Pyrobel Vision Line, which offer stylish options for frameless glass partitions with high fire ratings. You can find out more about these advanced products, which can be supplied by Tufwell, here.
For more information on fire glass products, to request a quote or to place your order, contact Tufwell Glass today.