Earlier this week I was reading through an article about residential fire protection and noticed a commentator calling out the serious maintenance obligations and malfunctioning potential of residential or commercial fire sprinklers. His argument was that malfunctions – and the subsequent water damage – were reason enough to dismiss the growing consensus around the safety benefits of fire sprinkler systems. I’m going to take this opportunity to dismiss some of these concerns.
With the increase in popularity (or regulatory requirement) for fire sprinkler systems in homes and commercial buildings, there is a lingering suspicion that sprinkler head error or unforeseen system malfunctions will lead to substantial water damage absent of a fire emergency. This is commonly called accidental leakage or discharge.
To be clear, the rate of fire sprinkler system malfunction is extremely rare. According to the American Fire Sprinkler Association, the odds of malfunction not resulting from direct human error are around 1 in 16 million. To put that in perspective, sprinkler systems are 16x less likely to malfunction than you are of being struck by lightning. Systematic leaks are also no more likely to be found in the plumbing than from a faulty sprinkler head. Pipe malfunctions, or leaks springing from the pipes that carry water to the system, do happen though they are more commonly associated with much older structures as compared to new, modern systems.
Five common fire sprinkler malfunctions:
• Overheating
• Freezing
• Corrosion
• Mechanical damage
• Human sabotage or error
Overheating: This is generally the result of sprinkler heads being installed in locations where ceiling temperatures exceed the sprinkler’s heat sensitivity during high heat times in the summer or in facilities with high temperature operations. While definitely a concern, most systems are engineered to take ceiling temperatures into consideration and are rated to handle even the highest summer temperatures. In this scenario, if ceiling temperatures can exceed 155 degrees, the most common sprinkler head temperature, then a 200 degree or 286 degree head is installed.
Freezing: In the exact opposite scenario, if wet systems are installed in facilities with extreme cold temperatures such as non-insulated buildings the pipe or sprinkler heads can freeze and crack. After thawing the system may then leak. This situation is as old as fire sprinklers themselves. Common remedies include anti-freeze solutions added to the pipes, adding insulation around the system, or installing dry fire sprinklers that leverage air pressure and specially designed valves to keep water out of the system until needed.
Corrosion: As with most water systems, corrosion can build up over time and impact the functionality of the system or eat through the pipe. Annual inspections and replacement of corroded components can quickly remedy this situation.
Mechanical Damage: This covers a variety of potential issues including over-tightening of fittings, improperly installed sprinkler heads (for instance, not using Teflon tape to seal the threads), and a variety of very uncommon installation or maintenance errors. Using a qualified and licensed sprinkler contractor can limit the likelihood of this type of malfunction.
Human sabotage or error: Arguably the most common malfunction is the result of human error. Ever see a sign that looks like this:
(via to Kiss A Mezuzah blog on blogspot)
Yup, it’s there because people are … misinformed enough to actually hang items from a fire sprinkler designed to discharge water! Other common errors include hitting sprinkler heads with fork lifts, painting over them which distorts the ability to accurately respond to temperature, or generally doing other really stupid (and preventable) things.
The chance of a sprinkler head expelling water in the absence of a fire or one of those five options is so low it’s almost nonexistent.
The fire sprinkler industry helps prevent malfunctions and manufacturer’ error by following very strict quality control regulations and ensures all their products are tested and listed by Underwriters Laboratories (UL) and Factory Mutual Research Corporation (FM). In addition, the industry as a whole (in most municipalities) requires licensed, bonded, and insured contractors install and maintain the system.
Fore more information, see: