Fire Suppression Systems Training

Fire Sprinkler Systems - Function, Operation, and Restoration Considerations

Introduction:

Fire sprinkler systems are vital life safety devices designed to suppress or extinguish fires in their incipient stages. These systems play an essential role in minimizing property damage, reducing injuries, and saving lives. Understanding their operation, materials, and associated risks is essential for restoration professionals.  

Function and Impact:

• Primary Function: Fire sprinkler systems are designed to automatically discharge water upon detecting a fire, controlling or extinguishing it before it spreads.  

• Property Savings: According to the National Fire Protection Association (NFPA), fire sprinklers significantly reduce property damage in fires. Studies indicate that properties equipped with sprinklers experience, on average, a 60-70% reduction in property loss compared to those without. This translates to billions of dollars in property saved annually.  

Operation and Materials:

• How They Work:

  • Fire sprinkler systems are typically connected to a pressurized water supply.  

  • Sprinkler heads are heat-sensitive devices containing a glass bulb or fusible link.  

  • When a fire occurs, the heat activates the sprinkler head, causing the bulb to break or the link to melt.

  • Smoke detectors do not, and can not activate a fire sprinkler system.

  • This releases a plug, allowing pressurized water to discharge directly onto the fire.

  • Only the sprinkler heads exposed to sufficient heat will activate, minimizing water damage.  

  • There is no situation where 1 sprinkler head could activate all of the heads.

• Materials:

  • Piping: Commonly made of steel (black steel), copper, or CPVC (chlorinated polyvinyl chloride).  

  • Sprinkler heads: Brass or chrome-plated brass, with glass bulbs or fusible links.  

  • Valves and fittings: Typically made of brass, cast iron, or steel.

Types and Options:

• Wet Pipe Systems: The most common type, where pipes are constantly filled with pressurized water.  

• Dry Pipe Systems: Used in freezing environments, pipes are filled with pressurized air or nitrogen, and water is released when a sprinkler head activates.

• Pre-Action Systems: Used to protect sensitive equipment, these systems require both fire detection and sprinkler head activation before water is released.  

• Deluge Systems: All sprinkler heads discharge water simultaneously, used for high-hazard areas.  

• Residential Sprinkler Systems: Designed for homes, often using smaller diameter pipes and faster-acting sprinkler heads.

Water Category and Contamination:

• Category 3 Water: Water discharged from fire sprinkler systems is almost always considered Category 3 due to several factors:

  • Stagnation: Water in the pipes may sit for extended periods, leading to bacterial growth and sediment accumulation.  

  • Contaminants: Debris, rust, and cutting oils can occupy the system over time, without sufficient flushing periodically.

  • Fire Suppression Additives: Some systems may contain additives or chemicals to enhance fire suppression.

Because of these reasons, any water from a fire suppression system should be treated as contaminated, and all appropriate safety protocols should be followed.

It's advisable to have an IH inspect the water & collect samples to confirm category.

Contractor Caution and Demolition:

• Caution During Work:

  • Fire sprinkler systems are delicate and can be easily damaged.  

  • Accidental activation can cause significant water damage and disruption.  

  • Contractors must exercise extreme caution when working near sprinkler pipes and heads.

  • Contractors should have a reasonable plan to deal with a water released from a sprinkler line while working around them.

• Demolition Risks:

  • Striking pipes with tools or building materials can cause failures.

  • Paint and debris can clog sprinkler heads, impairing their activation.  (they should never be painted over)

  • Vibration associated with using saws can damage pipe connections & fittings causing activation.