What is fire rated glass, and does it really work? Just as the name implies, fire rated glass offers some level of protection in the event of a fire. It may seem like an unusual requirement for glass, but by slowing down the migration of smoke and flames, fire rated glass can improve the level of safety in commercial buildings and apartment complexes. When strategically incorporated into the architectural design, it can actually save lives in the event of a fire.
Fire Rated Glass Saves Lives
It goes without saying, that fire rated glass will not extinguish a burning fire. Nor will it warn the occupants of a building that they are in danger. However, it can play a huge roll in slowing down the spread of a robust fire. The architectural term for this is compartmentation. Fire rated walls and fire rated glass contain the fire and smoke to a limited area for a period of time.
Won’t Standard Glass do the Same Thing
Regular window glass offers very little protection against a roaring fire. It may look the same as fire rated glass but it won’t stand up to the extreme temperatures of a building fire. Most conventional glass will break when exposed to temperatures in excess of 250 degrees Fahrenheit. Tempered glass offers a little more protection and typically can withstand exposure to temperatures up to 500 degrees Fahrenheit.
Compare these to fire rated glass that has been engineered to endure temperatures of up to 1600 degrees Fahrenheit. It’s no surprise that architects specify this glass for commercial buildings and high-rise apartments where a raging fire can reach extreme temperatures in a hurry.
The Certification Process
To achieve its fire rating, fire rated glass must pass numerous tests conducted by an independent lab. The testing comprises of the entire window or door assembly including the glass, the framing, and door components. The entire unit is heated up in a furnace which simulates the extreme temperatures of a building fire. The fire rating will range from 20 minutes to 3 hours, depending on how long it takes for the glass to break.
The second step in the testing process is the “hose stream test”. This test is conducted immediately after the furnace test. The purpose of the test is to determine the integrity of the hot glass when subjected to water sprayed from a fire hose at a minimum pressure of 30 PSI.
The final test is the impact test which is a requirement for fire rated glass that will be used for doors, sidelites, and glass walls. The testing governs the amount of force the glass can withstand. A small bag of lead shot is dropped from various heights to determine the strength of the glass.