Researchers test current parking garage sprinkler designs

Large-loss fires in parking garages are a rarity but when they do occur, the consequences can be catastrophic — causing severe property damage, operational disruption, and challenging firefighting efforts. Take for instance a 2018 parking garage fire in Liverpool, England. It destroyed more than 1,000 vehicles before it was extinguished, and the damage to the garage itself was so extensive that the city had to demolish it.

The Liverpool parking garage did not have a sprinkler system, which allowed the fire to spread extensively before fire crews arrived. In the United States, parking garages are required to be equipped with sprinkler systems, however, experts in the field want to know if the minimum requirements currently in place are robust enough to prevent the type of extensive casualty experienced in Liverpool and similar events.

The Fire Protection Research Foundation (FPRF), an affiliate of the National Fire Protection Association (NFPA), is leading a research project to answer that question. Sponsored by the American Society for Health Care Engineering, the National Institute of Standards and Technology (NIST) and others, researchers ultimately will develop an engineering report that identifies gaps in sprinkler protection in parking garages and recommends appropriate requirements, if needed.

The project, Modern Vehicle Hazards in Parking Structures and Systems, is in its third phase, which involves a large-scale experimental fire test program. Tests are currently underway in Norway where a large open-air mock garage was built and designed to NFPA 88A, Standard for Parking Structures, requirements. The mock garage utilized in the experimental program is equipped with a sprinkler system designed to NFPA 13, Standard for the Installation of Sprinkler Systems, requirements for Ordinary Hazard Group 2 sprinkler design.

FPRF is conducting 10 vehicle fire tests: three tests assess how internal combustion engine (ICE) vehicles respond and six tests examine the patterns of battery electric vehicles (BEV). One additional test involves a two-vehicle car stacker system where two vehicles are stacked vertically — with a BEV placed above an ICE vehicle. Within this test program, a free-burn test for each vehicle type was conducted to set a baseline understanding of the hazard in order to measure the effectiveness of the sprinkler system in subsequent tests.

Victoria Lutz, senior research project manager at FPRF, explained that the tests are being administered under worst-case scenarios to effectively determine if current NFPA requirements are adequate.

“Given that a large percentage  of garages with sprinkler protection in the U.S. use a dry pipe sprinkler system, which means the system fills with air instead of water in areas that are subject to freezing, resulting in a delay in water delivery following  sprinkler activation,” Lutz says. “When the sprinkler activates, the air pressure drops and the piping will start to fill with water, but it can result in up to a 60-second delay. Which is the worst-case scenario we are testing to.”

As of press time, FPRF has conducted six out of the 10 scheduled tests and will be sharing early results at the NFPA Conference & Expo taking place June 16-18 in Las Vegas. The session, Fire and Life Safety Risk Management for Electric Vehicle Parking and Storage, is scheduled for June 17 at 2 p.m. Lutz will join a panel of speakers to explore fire and life safety risk management strategies for electric vehicles, including the importance of pre-planning, suppression system design and exposure to other hazards.