Author(s): Brian OConnor. Published on February 8, 2021.

In Compliance | NFPA 13

Fire protection for underground passenger rail systems

BY BRIAN O'CONNOR 

Last year, several significant passenger rail incidents and fires occurred, including a subway fire in March in New York City. One person died and 16 were injured in the incident. The investigation into the fire continues, but eyewitness accounts have indicated it was started by an arsonist aboard a train.

The New York fire was the kind of event that can strike fear in the hearts of rail users worldwide. Each day, hundreds of millions of people around the world rely on train and subway systems to get them to where they need to go. Before the global pandemic struck and reduced ridership in major cities to a trickle, the New York City subway system alone tallied an estimated 5.5 million passenger rides each day; the figure for Tokyo was 8.7 million. But while passenger rail systems are an efficient way of moving large numbers of people, they don’t come without risks.

NFPA 130, Standard for Fixed Guideway Transit and Passenger Rail Systems, addresses those risks. NFPA 130 defines a passenger rail system as a transportation system utilizing a rail guideway, operating on right-of-way for the movement of passengers within and between metropolitan areas, and consisting of its rail guideways, passenger rail vehicles, and other rolling stock. The rail system also includes power systems, buildings, stations, and other stationary and movable apparatus, equipment, appurtenances, and structures. The standard contains requirements for how to properly design and protect stations, trainways, vehicles, and the passengers inside those vehicles, and applies to new construction, extensions of existing systems, and new rolling stock.

For stations, NFPA 130 requires that sprinklers be installed in storage areas, trash rooms, areas of the station used for concessions, and any other similar areas with combustible loading. NFPA 130 also recommends that sprinkler be installed inside of combustible escalators, although many of today’s escalators are made of non-combustible or limited combustible construction. This recommendation comes from an incident in the London underground transit system, the Kings Cross Fire of 1987, which killed 31 people and injured more than 100. Investigators determined that the fire started under a wooden escalator. Fire alarm systems, portable fire extinguishers, standpipe and hose systems, as well as emergency ventilation systems are also required to be installed. Stations have many other life safety requirements regarding the construction and arrangement of paths of egress that work together with these fire protection systems to ensure rider safety.

NFPA 130 does not require sprinklers to be installed in trainways, the term used for the path of railway tracks. In NFPA 130, trainways are used primarily as an egress path in the event of an emergency where the train needs to be evacuated. NFPA 130 requires exits every 2,500 feet and cross passageways every 800 feet in enclosed trainways. Because trainways are used as a means of escape, they need to remain tenable in the event of a fire or other emergency. NFPA 130 ensures this happens by requiring ventilation based on the length of the enclosed trainway. If it is less than 200 feet, no ventilation is required; if it is between 200 feet and 1,000 feet, then natural or mechanical ventilation is needed; if it is greater than 1,000 feet, mechanical ventilation is required. NFPA 130 also requires additional safety features including exit signage, illumination, properly sized egress routes, as well as noncombustible rail ties and walking surfaces.

NFPA 130 acknowledges that passenger vehicles are a large source of fuel for a fire. The standard addresses this issue by preventing fire ignition and mitigating fire impact. These approaches are addressed through electrical safety measures as well as requiring the interior and exterior surfaces of the vehicles to go through extensive testing to ensure high levels of fire safety performance.

While both aboveground and underground passenger rail systems present unique and challenging scenarios, with the proper design and installation these systems can be safe and reliable means of transportation. 


Brian O’Connor is a technical services engineer at NFPA. NFPA members and AHJs can use the Technical Questions tab to post queries on NFPA 13 at
nfpa.org/13. Top photograph: Getty Images