Limit the chances of a fire sprinkler leak

If a fire sprinkler has discharged water in the absence of a fire, an investigation should be undertaken to determine why the sprinkler operated.

03/01/2001


If a fire sprinkler has discharged water in the absence of a fire, an investigation should be undertaken to determine why the sprinkler operated.

According to the National Fire Sprinkler Association (Wisconsin Chapter), the reasons typically are inadvertent overheating, freezing, mechanical damage, corrosion, or deliberate sabotage.

Overheating —Automatic sprinklers respond to heat, and cannot differentiate between "good heat" and "bad heat." If sprinklers are located close to unit heaters, under skylights and in other areas exposed to high heat, the applicable rules of NFPA Standard 13 Installation of Sprinkler Systems require that higher temperature rated sprinklers be used. This means that the solder elements or glass bulbs used as the operating mechanisms will be designed to activate at temperatures of 200%%MDASSML%%300 F (93%%MDASSML%%149 C) instead of the normal 155%%MDASSML%%165 F (68%%MDASSML%%74 C). If new sources of heat are added, a qualified contractor should be hired to make the necessary modifications. Temporary heat-producing sources such as construction lighting and television cameras have also been known to activate sprinklers.

Freezing —Most sprinkler systems are wet pipe systems, meaning that the piping is filled with water. If a system — or even a small portion of a system — is exposed to freezing temperatures, water in the piping can turn to ice, expanding in volume and producing thousands of pounds of pressure. Such pressures can break fittings, as well as force open the valve caps of sprinklers, resulting in apparent accidental discharge or leakage when the system thaws. A common cause of exposure of sprinkler pipe to freezing temperatures is the movement or removal of pipe installation and the subsequent failure to replace it.

Mechanical damage — Although it's obvious that a large force can immediately open a sprinkler, it is less obvious that a smaller impact can do the same thing over time. That's why it is important that sprinklers be carefully handled during the installation process, and that the proper wrenches be used during their installation. Special wrenches are often required by the manufacturers' literature to reduce the possibility of slippage that can damage the sprinkler operating mechanism, potentially resulting in a release of parts weeks or months later. Building renovations can also result in impacts of sprinklers, leading to an inadvertent discharge or leakage at a later date.

Corrosion — Corrosion can result in a weakening of parts, and a subsequent release of water. This situation can occur among very old sprinklers, or sooner with sprinklers installed in a harsh environment. Many fire codes require enforcement of NFPA 25Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems . This standard requires that the building owner replace sprinklers that exhibit corrosion, loading, or other damage.

Deliberate sabotage — Deliberate acts of sabotage must also be considered when investigating the reasons for sprinkler discharge. Vandalism and insurance fraud have been found in the past to be motivations for tampering with sprinklers.

Manufacturing defect — Although very rare, the possibility of a manufacturing defect can be considered when all other potential reasons for inadvertent operation have been ruled out. This case could take the form of a problem in loading or tolerances on the parts. The sprinkler manufacturer should be contacted, and arrangements can be made for professional analysis.

The NFSA is a trade association comprised of installers and manufacturers of fire sprinklers and related equipment and services. Visit their web site at nfsa.org .





No comments
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2015 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
Safer human-robot collaboration; 2017 Maintenance Survey; Digital Training; Converting your lighting system
IIoT grows up; Six ways to lower IIoT costs; Six mobile safety strategies; 2017 Salary Survey
2016 Top Plant; 2016 Best Practices on manufacturing progress, efficiency, safety
Mobility as the means to offshore innovation; Preventing another Deepwater Horizon; ROVs as subsea robots; SCADA and the radio spectrum
Future of oil and gas projects; Reservoir models; The importance of SCADA to oil and gas
Big Data and bigger solutions; Tablet technologies; SCADA developments
Automation modernization; Predictive analytics enable open connectivity; System integration success; Automation turns home brewer into brew house
Commissioning electrical systems; Designing emergency and standby generator systems; Paralleling switchgear generator systems
Natural gas for tomorrow's fleets; Colleges and universities moving to CHP; Power and steam and frozen foods

Annual Salary Survey

Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.

There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.

But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.

Read more: 2015 Salary Survey

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.
Motion control advances and solutions can help with machine control, automated control on assembly lines, integration of robotics and automation, and machine safety.
Compressed air plays a vital role in most manufacturing plants, and availability of compressed air is crucial to a wide variety of operations.
Maintenance Manager; California Oils Corp.
Associate, Electrical Engineering; Wood Harbinger
Control Systems Engineer; Robert Bosch Corp.
click me