Study: Hybrid suppression systems need own standards

Part water mist, part gas suppression systems, the new technology isn’t addressed by current NFPA standards, new research concludes
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Wednesday, July 30, 2014

QUINCY, Mass.—A hybrid fire suppression system is a combination water mist and gas suppression system, and because this new technology is a hybrid, there is no one NFPA standard that covers it. Should there be? A recently released study looked to answer that question.

The Fire Protection Research Foundation initiated the project, which is titled a “Literature Review on Hybrid Fire Suppression Systems.” The foundation, based here, is an affiliate of the National Fire Protection Association.

Amanda Kimball, research manager for the foundation, talked to Security Systems News about the need for the study, authored by two members of the fire protection engineering department at the University of Maryland in College Park.

“Water mist is covered by NFPA 750 and gaseous suppression systems are covered by NFPA 2001. So the big question was: If these were to be covered in the standards process, where exactly would they fit?” Kimball said. “Would they fit better with water mist, would they fit better with gaseous suppression, or are they unique enough to deserve their own document?”

The answer to that question affects the way such hybrid systems are installed and used, the study says. It concluded that changes should be made in the existing standards or a new standalone standard should be developed.

Kimball said that developing clear standards should help the market for hybrid systems. She said end users are more likely to want to install new technology “if there is a specific standard that covers [it].”

Hybrid systems are a new fire suppression technology used in such applications as machinery enclosures and computer server rooms.

“These new hybrid systems utilize both an inert gas (typically nitrogen) as well as a fine water mist to provide fire suppression and/or extinguishment more efficiently than standalone inert gas or water mist systems,” the study says.

Kimball said the systems “use less water than a typical water mist system.”

Manufacturers, including Ansul and Victaulic, sell hybrid systems to the general public, according to the study. Victaulic advertises its product as producing “nearly zero wetting of protected areas” and eliminating “costly cleanup or equipment replacement” in the event of a fire.

But because the hybrid system doesn’t fit under any one standard, some “manufacturers are ‘mixing and matching’ requirements for water mist systems and inert gases to suit their needs,” the study asserts.

Kimball explained: “One of the reasons this was brought to NFPA is that there’s a bit of cherry-picking going on right now, taking some of this standard and taking some of that standard.”

She said concerns raised by FM Global, a Rhode Island-based provider of comprehensive commercial and industrial property insurance, factored into the study.

“[FM Global] had developed an approval standard for these types of systems because they were seeing them in their properties or they were proposed to be installed in the properties that they insured,” Kimball said. “So they did a test program to try and look at the physics behind how these systems worked.” Much of the information in the study came from FM Global, she said.

What conclusions and recommendations did the study reach?

The key conclusion was that “there is significant need for a standard that covers hybrid suppression systems.”

That’s because the study found that while the systems share many similarities with traditional water mist and inert gas systems, “there are clearly differences that must be considered in [their] installation, inspection and application.”

The study recommended that either a new independent standard be developed for the hybrid systems or additions be made to either NFPA 750 or NFPA 2001.

However, if the decision is made to add hybrid systems to either NFPA 750 or NFPA 2001, the technical committee responsible for the standard selected would need to add new members with expertise on the installation, operation and maintenance of the hybrid systems, the study said.

Also, any addition to the current standards “must include separate chapters on system definitions, system design and system inspection, testing, maintenance and training,” the study concluded.