A word of caution about sprinkler tradeoffs
Today, active fire protection systems such as sprinklers have proven to be helpful in containing the fire to its room of origin. However, an over-reliance on sprinklers can also be dangerous, especially when used as a tradeoff to eliminate fire-resistive glazing in one- to two-hour rated exit enclosures and fire-rated walls.
Sprinklers and active fire protection systems are designed to suppress fire, and require an outside trigger in order to operate. To be effective in the event of a fire, regular maintenance must also be performed on the sprinkler system to ensure it works and has sufficient water supply and pressure. On the contrary, passive or built-in fire protection systems such as fire-resistive glazing contain fire, smoke, and heat to the point of origin without the need for any outside triggers or maintenance.
One is not more important than the other—both active and passive fire protection systems are equally important in containing and suppressing the fire. This approach, known as balanced fire protection or safety layering, is more important than ever when sprinklers fail—which, as the U.S. National Fire Protection Association (NFPA) has reported, can and has happened. (John R. Hall’s report, “U.S. Experience with Sprinklers,” was published by NFPA in 2013.)
In the same NFPA report, it was noted most sprinkler failures occurred because the system was shut off, and the majority of sprinkler ineffectiveness was caused because water did not reach the fire or not enough water was released. Damage to the sprinkler system or decreased water pressure is especially a concern during natural disasters such as hurricanes or earthquakes, where the threat of fire is increased.
Having passive or built-in fire-resistive building materials that perform 24/7 without any triggers gives building occupants the best chance to exit the building safely, and minimizes the danger to firefighters responding to the scene. As is stated in a white paper from Fire Safe North America (FSNA):
The concern is not so much that a properly maintained automatic sprinkler system will fail, but that a natural disaster, human error or lack of maintenance could disable the system to the point where additional layers of protection may be the only measures preventing or delaying a building or an entire block from being destroyed by fire. When those safety layers do not exist, the building will not be able to withstand as big of a fire and will fail sooner, putting occupants and especially firefighters at great risk. (To read it, visit firesafenorthamerica.org/about/about/white-paper.)
Conclusion
Architects can gain some perspective from learning about the devastating effects of radiant heat on people and property from the firefighters who have experienced it first-hand. In a way, the building materials architects specify are the first line of defense when it comes to limiting radiant heat, and offer significant assistance to firefighters in their rescue and fire confinement objectives. Advanced life-safety building products, such as fire-resistive glazing systems meeting CAN/ULC-S101 criteria, enable architects to combine maximum fire protection with vision, transparency, and all the esthetic benefits glass has to offer.
Diana San Diego has more than 11 years of experience in the architectural glazing industry, and more than 13 years of experience in public relations and marketing. As the vice-president of marketing at SAFTI FIRST, a manufacturer of fire-rated glass and framing systems, she oversees the advertising, content management, media relations, promotional activities, and communication initiatives for the company. San Diego has contributed articles to various publications and is involved in creating and promoting educational programs. She can be reached at dianas@safti.com.
