DO YOU KNOW YOUR E FROM YOUR EI?

With three different fire glass classifications available, each with its own performance characteristics, there can be confusion regarding which classification should be specified and where. Here, Pyroguard provides some clarity.

According to BS EN 13501-2, there are three main classifications of fire safety glass to be aware of: E (Integrity), EW (Integrity & Radiation) and EI (Integrity & Insulation).

E – Integrity

E offers the base level of fire performance and is also the minimum requirement stated by the UK Building Regulations. While it provides an effective barrier against smoke and flame, it does not prevent the transmission of heat.

EW – Integrity & Radiation

EW represents a step up in the level of protection offered. Fire glass that achieves the EW classification will maintain the same level of protection against smoke and flame as E but, in addition, will also deliver a reduction in the amount of radiant heat transmitted to the protected side. Specifically, EW keeps the amount of radiant heat to below 15kW/m².

EI – Integrity & Insulation

The EI classification offers the highest level of protection. As well as providing a robust barrier against smoke and flame, EI also delivers a significant reduction in the amount of heat transferred through the glass, keeping the average temperature of the unexposed side to below 140^oC. In simpler terms, this means that there could be a raging fire on one side of the glass, with temperatures above 800^oC, and yet you could make an escape on the unexposed side, remaining protected from the heat.

Of course, it is important to remember that, while the type of protection offered is determined by the product’s classification, the length of time for which this protection can be maintained will vary. Typically, with fire rated glass, from 30 minutes all the way up to 180 minutes.

Having an understanding of the three fire glass classifications and their performance characteristics is key if architects are to make more informed specification decisions. For example, despite E being the minimum requirement stated by Building Regulations, there are applications where higher performance products would be better suited, such as data centres, museum archive or evacuation zones within a hospital.

In fact, Pyroguard has witnessed a recent shift within the industry with more customers installing EW and EI glass, perhaps signalling an increased awareness of higher performance products and a greater duty of care in project design and building maintenance.

For more information, please visit: www.pyroguard.eu.