Fire Rated Glass: What You Need to Know

Fire rated glass as the name suggests, is different from ordinary glass.  Fire rated glass acts as a barrier to the spread of flames and smoke. In the world of fire protection, this is known as “compartmentation.” Like most glass, fire-rated glazing also allows light and visibility for aesthetic or security reasons.

What makes fire rated glass so great? Unlike sprinklers or other protection systems, fire-rated glass protects your office 24 hours a day. If there is a power failure, a loss of water pressure, or a human error that interferes with the sprinklers, fire-rated glass will not be affected and will continue to perform as needed. Staying in place during a fire may sound like a fairly simple task, but ordinary glass cannot do this.[1]

Difference between fire-protective and fire-resistive

The first thing to consider when specifying rated glass is what you are trying to protect against. There is an important difference between fire-protective glass and fire-resistive glass and building codes are very specific about where each is to be used.

Fire-protective glass prevents the spread of fire and smoke.

However, it will not prevent radiant heat transfer. That means that as the glass heats up from fire on one side, objects on the other side of the glass will feel the heat. Materials for this type of glass include traditional wired glass, glass ceramics and specially tempered glass. Fire-protective glass can typically be used where building codes allow “opening protective” assemblies. While such glazing is available with fire ratings ranging from 20 to 180 minutes, it is subject to area and size limitations under the applicable building code and/or authority having jurisdiction.

Fire-resistive glass provides the same defense against flames and smoke but adds further protection by blocking the transfer of radiant and conductive heat.

As such, objects on the protected side do not get hot enough to spontaneously combust. Fire-resistive glass products generally are multi-laminates incorporating several layers of glass with fire-resistive inter-layers. They are typically suitable where building codes require an assembly designated “fire resistant” to enclose a space. Examples include wall applications requiring a 60-minute or greater fire rating that must meet temperature-rise criteria, such as stairwells, exit access corridors, or other fire barriers dividing interior construction.

Fire Rated Glass Testing

What is a fire rating? A fire-resistance rating typically means the duration for which a passive fire protection system can withstand a standard fire resistance test. This can be quantified simply as a measure of time, or it may entail a host of other criteria.

Fire rated glass is tested the same way that other fire rated materials are tested. A wall is built in the side of a furnace. The glass systems are installed into the wall just like they would be installed in the field. Then a fire is created in the furnace at the prescribed temperature and left to burn for the amount of time required for the test. The glazed assembly must remain intact as specified in the testing criteria.[2]

Contact Cube7 Interiors today to discuss your requirements

References:

[1] http://www.fireglass.com/glass/School-Handbook.pdf

[2] https://www.archtoolbox.com/materials-systems/doors-windows/fire-rated-glass-and-glazing.html