Clear Fire-Resistant Glass (also called Fire Rated Glass) is the only alternative to a solid wall. Developed by Pilkington Glass more than 40 years ago, Pilkington Pyrodur® and Pyrostop® were amongst the first clear fire-resistant (fire rated) glass options on the market. Designed to look like normal float glass, they are anything but. The glass is designed to act as a barrier resisting the spread of fire for a period of time measured in 30 minute increments; 30, 60, 90, 120.
This ability to resist the physical properties of fire is known as “Integrity” and is represented by the Pilkington Pyrodur® range of products. Pilkington Pyrostop® blocks flames and smoke but is also designed to withstand radiant heat by providing thermal insulation, which is known as “Insulation”.
These are British Standard (BS) classifications and are classified as E (Integrity) and EI (Integrity and Insulation) according to the European Norm (EN) Standards.
To establish the performance of a particular glass it can be tested or assessed by a specialist as part of a glazing system, including frame, glazing materials, fixing etc. Pilkington prefer empirical evidence for their products, especially in such a critical area as fire, and so always test each product with every permutation of frame and glazing material and in every conceivable situation. The test takes the form of submitting the glass within the frame into a furnace. Thermocouples are attached to the glass to record temperature at various points on its surface and it is exposed to temperatures of close to 1000 °C.
The rate of increase in temperature fluctuates to simulate the difference between a gas ignited and oil ignited fire. In the case of Integrity (E) only the glass simply needs to remain intact for a period of 30, 60 etc., minutes during this fire, with no flaming on the non-fire side.
For Insulation (EI) to be achieved, the glass not only needs to remain intact but also the temperature on the non-fire side needs to remain below a mean of 140°C across all the thermocouples and no higher than 180°C on any one. This allows exit and access routes to be maintained in the building during a fire in order for people to escape and fire fighters to enter. It also helps prevent the spread of fire from one part of a building to another or indeed to adjacent buildings.
T A Anders Limited is a Licensed Supplier of these fire-resistant glass products for Pilkington. At our processing facility in Trafford Park, Manchester, we stock the entire range, process, distribute and can install if required.