Sprinkler Systems

Why People Don’t Install Fire Sprinkler Systems:

5 Misconceptions That Could Kill You

Not everybody has a fire sprinkler system installed at home. In fact, it may be safe to say that most people don’t have fire sprinkler systems. Why, if fires are so common and so dangerous, don’t more people have fire sprinkler systems installed? Why isn’t it a law?

In fact, many cities and regions throughout the U.S. have made it mandatory to install fire sprinkler systems-and fire chiefs in many more areas are calling for just such laws. But there are also many misconceptions that keep people from installing fire sprinkler systems. Here are five of the more common ones:

1. A fire sprinkler causes more water damage than it’s worth

Not true. Each fire sprinkler in the system is designed to go off individually. The heat from a fire activates only the fire sprinkler directly above it. Water damage is minimal. In the case of more severe fires, where more than one fire sprinkler is activated, the water damage is much less than the fire damage would have been without the fire sprinkler system.

2. I’ve got smoke alarms-so I’m safe

This is one of the most dangerous misconceptions out there. A smoke alarm does not provide full protection against fire. Because inattention is a frequent cause of fire, many start at night. Even though smoke alarms are loud, it can take several minutes for a person to wake, realize what’s going on, and get out of the house when a fire starts. Those few minutes can be all a fire needs to block escape routes.

3. A fire sprinkler installation is too expensive

Installing a fire sprinkler system costs about as much as installing new carpets. Not as cheap as a set of new fire alarms, true. But the protection they provide to your family is worth any price.

4. A fire sprinkler system isn’t effective at controlling fires

Again, not true. Fire sprinkler systems are more effective than the fire department-and they use a tiny fraction of the water. The reason they are so effective is that they stop fires almost immediately, before they have a chance to get out of control. By the time the fire department arrives at a burning house, the fire has almost always grown much larger and is much more difficult to control.

5. A fire sprinkler in every room will look unsightly

Actually, most fire sprinkler manufacturers make specially-designed fire sprinkler heads that blend in with your walls and ceiling. Residential fire sprinklers can be installed in a recess and covered with a special cap that drops off in case of fire, covering the fire sprinkler head in the meantime so that it blends completely with the ceiling. These caps come in many colors to match your paint, or they can be custom-ordered.

Types of Sprinkler Systems

Our staff is qualified to perform fire sprinkler inspections for all types of sprinkler systems. We can plan a comprehensive fire sprinkler inspection program that will suit the needs of any facility.

Wet Sprinkler System

Wet pipe systems are the most common fire sprinkler system. A wet pipe system is one in which water is constantly maintained within the sprinkler piping. When a sprinkler activates this water is immediately discharged onto the fire.


System simplicity and reliability:
Wet pipe sprinkler systems have the least number of components and therefore, the lowest number of items to malfunction. This produces unexcelled reliability which is important since sprinklers may be asked to sit in waiting for many years before they are needed. This simplicity aspect also becomes important in facilities where system maintenance may not be performed with the desired frequency.

Relative low installation and maintenance expenses:
 Due to their overall simplicity, wet pipe sprinklers require the least amount of installation time and capital. Maintenance cost savings are also realized since less service time is generally required compared to other system types. These savings become important when maintenance budgets are shrinking.

Ease of modification:
Wet pipe fire sprinkler systems are advantageous since modifications involve shutting down the water supply, draining pipes and making alterations. Following the work, the system is pressure tested and restored. Additional work for detection and special control equipment is avoided which again saves time and expense.

Short term down time following a fire:
Wet pipe sprinkler systems require the least amount of effort to restore. In most instances, sprinkler protection is reinstated by replacing the fused sprinklers and turning the water supply back on. Pre-action and dry-pipe systems may require additional effort to reset control equipment.

  • Wet pipe systems are not suited for sub-freezing environments.
  • There may also be a concern where piping is subject to severe impact damage and could consequently leak.

Dry Pipe Fire Sprinkler System

A dry pipe sprinkler system is one in which pipes are filled with pressurized air or nitrogen, rather than water. This air holds a remote valve, known as a dry pipe valve, in a closed position. Located in a heated space, the dry-pipe valve prevents water from entering the pipe until a fire causes one or more sprinklers to operate. Once this happens, the air escapes and the dry pipe valve releases. Water then enters the pipe, flowing through open sprinklers onto the fire. Keep in mind that if your building has a dry pipe fire sprinkler system, it is the OWNER’S responsibility to drain the low point drains regularly, especially before freezing weather. If you aren’t sure how to drain your low points, refer to our drum drip care and maintenance sheet.

  • Dry pipe sprinkler systems provide automatic protection in spaces where freezing is possible. Typical dry pipe installations include unheated warehouses and attics, outside exposed loading docks and within commercial freezers.
  • Many people view dry pipe sprinklers as advantageous for the protection of collections and other water-sensitive areas. This perceived benefit is due to a fear that a physically damaged wet pipe system will leak while dry pipe systems will not. In these situations, however, dry pipe systems will generally not offer any advantage over wet pipe systems. Should impact damage happen, there will only be a mild discharge delay, i.e. 1 minute, while air in the piping is released before water flow.
  • With the exception of unheated building spaces and freezer rooms, dry pipe systems do not offer any significant advantages over wet pipe systems.

  • Increased complexity: Dry pipe systems require additional control equipment and air pressure supply components which increases system complexity. Without proper maintenance this equipment may be less reliable than a comparable wet pipe system.
  • Higher installation and maintenance costs: The added complexity impacts the overall dry-pipe installation cost. This complexity also increases maintenance expenditure, primarily due to added service labor costs.
  • Lower design flexibility: There are strict requirements regarding the maximum permitted size (typically 750 gallons) of individual dry-pipe systems. These limitations may impact the ability of an owner to make system additions.
  • Increased fire response time: Up to 60 seconds may pass from the time a sprinkler opens until water is discharged onto the fire. This will delay fire extinguishing actions, which may produce increased content damage.
  • Increased corrosion potential: Following operation, dry-pipe sprinkler systems must be completely drained and dried. Otherwise remaining water may cause pipe corrosion and premature failure. This is not a problem with wet pipe systems where water is constantly maintained in piping.

Pre-Action Fire Sprinkler System

Pre-action fire sprinkler systems employ the basic concept of a dry pipe system in that water is not normally contained within the pipes. The difference, however, is that water is held from piping by an electrically operated valve, known as a pre-action valve. Valve operation is controlled by independent flame, heat, or smoke detection.

Two separate events must happen to initiate sprinkler discharge. First, the detection system must identify a developing fire and then open the pre-action valve. This allows water to flow into system piping, which effectively creates a wet pipe sprinkler system. Second, individual sprinkler heads must release to permit water flow onto the fire.

In some instances, the pre-action system may be set up with a double interlock in which pressurized air or nitrogen is added to system piping. The purpose of this feature is two-fold: first to monitor piping for leaks and second to hold water from system piping in the event of inadvertent detector operation. The most common application for this system type is in freezer warehouses.

  • The dual action required for water release: The pre-action valve must operate and sprinkler heads must fuse. This feature provides an added level of protection against inadvertent discharge. For this reason, preaction systems are frequently employed in water sensitive environments such as archival vaults, fine art storage rooms, rare book libraries and computer centers.
  • Higher installation and maintenance costs: Pre-action systems are more complex with several additional components, notably a fire detection system. This adds to the overall system cost.
  • Modification difficulties: As with dry-pipe systems, pre-action sprinkler systems have specific size limitations which may impact future system modifications. In addition, system modifications must incorporate changes to the fire detection and control system to ensure proper operation.
  • Potential decreased reliability: The higher level of complexity associated with pre-action systems creates an increased chance that something may not work when needed. Regular maintenance is essential to ensure reliability.

Deluge Fire Sprinkler System

A deluge system is similar to a pre-action system except the sprinkler heads are open and the pipe is not pressurized with air.

Deluge systems are connected to a water supply through a deluge valve that is opened by the operation of a smoke or heat detection system. The detection system is installed in the same area as the sprinklers. When the detection system is activated water discharges through all of the sprinkler heads in the system.

Deluge systems are used in places that are considered high hazard areas such as power plants, aircraft hangars and chemical storage or processing facilities. Deluge systems are needed where high velocity suppression is necessary to prevent fire spread.

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