Automatic Sprinklers In Buildings
One of the most effective fire protection elements in buildings is automatic sprinklers. When sprinklers cover an area of fire origin, they operate in 95% of all reported structure fires that are...
One of the most effective fire protection elements in buildings is automatic sprinklers. When sprinklers cover an area of fire origin, they operate in 95% of all reported structure fires that are large enough to activate the sprinklers.
Sprinklers save lives, protect property from fires, and are reliable. When in operation, sprinklers are effective 96% of the time.
The NFPA has no record of a fire killing three or more people in a completely sprinklered building where the system was properly operating, except in an explosion or flash fire, or where civilians or firefighters were killed while engaged in fire suppression operations.
An estimated 64% of reported 2006 structure fires in health care properties showed automatic extinguishing equipment present. In 2003-2006 health care structure fires, 93% of the automatic extinguishing equipment reported was sprinklers. The majority of 2006 reported structure fires in manufacturing properties, cold storage warehouses, hotels and motels, and public assembly properties also showed automatic extinguishing equipment present. In 2003-2006, sprinklers accounted for more than 90% of the automatic extinguishing equipment present for each of these property types.
Sprinklers are still rare in many places where people are most exposed to fire, including schools, offices, most stores and especially homes - where most fire deaths occur. There is considerable potential for expanded use of sprinklers to reduce the loss of life and property to fire.
When sprinklers fail to operate, most often the reason is shutoff of the system before fire began, as may occur in the course of routine inspection maintenance. Other leading reasons are lack of maintenance, inappropriate system for the type of fire, and manual intervention that defeated the system. Only 3% of sprinkler failures are attributed to component damage.
When sprinklers operate ineffectively, the reason usually involves insufficient water applied to the fire, either because water did not reach the fire or because not enough water was released. Other reasons were an inappropriate system for the type of fire, lack of maintenance, and manual intervention that defeated the system.
When people die in fires despite the presence of operating sprinklers, it is often because they are close to the fire when it begins or because they had vulnerabilities or limitations before fire began (44% of fatal victims when sprinklers operate are age 65 or older).
When wet pipe sprinklers are present (excluding structures under construction and cases of failure or ineffectiveness because of a lack of sprinklers in the fire area), the chances of dying if a home fire occurs are reduced by 80%, and the average property loss per fire is cut by 45-70% for most property classes, compared to reported fires where no automatic extinguishing equipment is present.
There are certain fire situations where even a complete sprinkler system will have limited impact:
- explosions and flash fires that may overpower the system;
- fires that begin very close to a person or unusually sensitive and expensive property where fatal injury or substantial property loss can occur before sprinklers can react; and
- fires that originate in unsprinklered areas (e.g., concealed wall spaces) or adjacent properties (e.g., exposure fires), which may grow to unmanageable size outside the range of the sprinkler system.
- sprinkler standards are based on design fires less severe than explosions or flash fires, as is normally the case;
- sprinkler objectives are defined in terms of a design fire area larger than the distance implied, by a victim intimate with ignition; or
- sprinkler standards exclude certain potential areas of fire origin from their definition of complete coverage, which is typically but not always the case.
- distinguish between human and mechanical problems because they require different strategies;
- include both as concerns to he addressed when deciding when and how to install, maintain, and rely on sprinklers and other automatic extinguishing systems;
- strive to use performance analysis in assessing any other element of fire protection; and
- remember that the different elements of fire protection support and reinforce one another and so must always be designed and considered as a system.