Fire Sprinkler Systems are one of the most effective ways of minimising property damage and the risk to life from a fire.  In a future article we will talk about how they work, but this article will focus on what to do after a sprinkler system has been activated.  There are two ways that this could occur, one is from a fire and the second is by interference by a person.

Some of you will wonder why we aren’t speaking about a failure of the sprinkler system, that is because this type of failure is extremely rare. One study from the USA concluded that fire sprinkler failures are no more likely or severe than standard plumbing failures.

So how does a sprinkler system get activated by human interference? 

Here are a number of scenarios that our customers have experienced:

  • The sprinkler head in a car park is hit by the roof rack on a 4WD vehicle
  • The sprinkler head is hit by a fork lift loading the top level of some pallet racking
  • The sprinkler system is hit by a rock thrown by vandals
  • A painter repairing the ceiling uses a hot air gun too close to the sprinkler head
  • A guest in a hotel room used the sprinkler to hang some clothes from, the coat hanger activated the sprinkler system.

When a sprinkler system has been activated it is critical that the water supply to the system is isolated as quickly as possible.  This should only be done once it has been confirmed that it is an accidental activation not a real fire event.  The Fire Service will attend and isolate the sprinkler system but this could take up to 10 minutes.  Therefore we recommend that Wardens are trained in how to turn off the isolation valve in the sprinkler system. 

So what do you do after the water has stopped flowing?

The activation of a sprinkler in a car park will eventually be dealt with by the drainage system.  Although initially it may struggle to keep up with the inflow of water from the sprinkler system.

The activation of a sprinkler in a warehouse has two impacts, the first is the water damage to the goods being stored and the second is flooding of the floor.

A flooded concrete floor can be drained using wet vacuums, water brooms or normal brooms to clear away the bulk of the water.  Then a combination of high volume air dryers and dehumidifiers can be used to dry out the concrete and remove the moisture from the air in the building.

Depending upon the type of stock held in the warehouse it may need to be repackaged or disposed of.  Fortunately the damaged stock will be localised around the activated sprinkler, not throughout the warehouse.

The activation of a sprinkler in an office, hotel or apartment is much more catastrophic.  If the activation is in a multilevel building then the water can flow through floor penetrations from the main floor to those below. This can increase the affected area well beyond the location of the activated sprinkler head.

If the water is flowing through floor slabs then the first thing to do is isolate all electrical fittings and circuits that may be impacted by the water.

Next, the bulk of the water needs to be removed using wet vacuums.  Then the air dryers, blowers and dehumidifiers can be used to dry out all carpets, furniture and fittings.

Unfortunately most modern furniture is made of chipboard which is effectively destroyed by water and will need to be disposed of.

Also computer and other electrical and electronic equipment may be destroyed by water.  It is therefore critical that business data contained on computers is regularly backed up off site so that the resulting damaged computers do not irreversibly impact on the business.

There are specialist companies that can assist with the clean up of flooded workplaces.  Don’t wait for the event, add their contact details to your Emergency Plan.  Your insurance company may be able to help you with these contact details.

Myths

Myth: The water damage from fire sprinklers is worse than a fire.

Fact: A fire sprinkler activates during the early stages of a fire before it grows and spreads. A sprinkler will control or extinguish a fire with a tiny fraction of the water that would be used by fire department hoses. Typically, only the sprinkler closest to the fire will activate, spraying water directly on the fire, not the rest of the house.

Myth: Fire sprinklers go off accidentally, causing unnecessary water damage.

Fact: Accidental fire sprinkler discharge is extremely rare. One study concluded that home fire sprinkler accidents are no more likely or severe than standard home plumbing mishaps.

Myth: All sprinkler will be activated at once

Fact: Each individual sprinkler must be activated by the temperature at the sprinkler exceeding a certain level.  If the temperature doesn’t reach the required level the sprinkler will not be activated.

How much water?

In the above video we show the activation of a drencher system, this system has open sprinkler heads that are all manually operated.  It gives you an understanding of how much water comes out of a sprinkler head.  Typically there is a flow of 60 litres per minute from each sprinkler head.