Anthony Caranci pulled down a handle Wednesday morning on a first-floor wall inside the 275-year-old Christ Church, and a squat red pump in the basement roared to life.
Jets of water shot forth from more than two dozen nozzles surrounding the steeple, enveloping one of Philadelphia’s most historic structures in a curtain of mist.
Caranci and his colleagues from Oliver Fire Protection in King of Prussia were testing the equipment to see if any nozzles needed to be replaced as the church prepares to renovate its leaning steeple. In the wake of the fire that savaged Notre Dame Cathedral in Paris, the test also was meant to demonstrate that the church in Old City was ready for the worst.
The water curtain, last upgraded 15 years ago, is designed to protect Christ Church’s exterior from sparks should any nearby buildings catch fire. The redbrick structure also is protected from within by a sprinkler system — unlike the ancient wooden roof of Notre Dame, where the blaze is thought to have begun.
To the dismay of preservation advocates, many historic buildings in the United States — houses of worship in particular — have gaps in fire protection similar to Notre Dame.
Churches are especially vulnerable to fire for a variety of reasons, said Bob Jaeger, president of Partners for Sacred Places, a Philadelphia-based nonprofit that helps preserve historic religious structures.
In addition to the maintenance challenges that face any older building, many churches struggle with shrinking congregations. That means less money to upgrade infrastructure. It also can mean staff cuts, raising the risk that a fire can begin when no one is on site, allowing it to grow to the point of no return.
“There’s nobody there to smell it,” said Jaeger, whose organization helped fund sprinkler upgrades at Christ Church.
Notre Dame typically had no shortage of people on site, though like many churches, it was built with a warren of enclosed attic spaces where a blaze could grow undetected.
“Churches have organ chambers, closets, attic spaces,” Jaeger said. “They’re kind of closed up. Nobody sees it. It can get to the point where it’s hard to stop it.”
A fire that burns undetected for long enough in an enclosed space can lead to a dangerous condition called flashover, said fire protection engineer John Devlin, vice president of the Baltimore-based engineering firm Jensen Hughes.
“You can get temperatures high enough that all the combustibles in that space can ignite simultaneously,” Devlin said.
Still unclear is what sparked the blaze in Paris. Dozens of investigators are picking through the ashes, but a full analysis likely will take weeks.
Officials have said an accident connected to renovation work was a possible cause.
That could mean many things, said Jim Milke, chair of the University of Maryland’s department of fire protection engineering. Workers may have been removing paint with a heat torch. Someone may have been welding or working with hot tar.
Or there may have been no spark at all. Linseed oil, used in wood finishes, generates heat as it degrades, as many a homeowner has discovered by accident. With enough time, a bucket of rags soaked in the pungent fluid can spontaneously combust. That is what caused the 1991 fire at One Meridian Plaza, killing three firefighters.
Most of the 38-story Meridian building was not equipped with sprinklers; the fire prompted a new law requiring sprinklers in nonresidential skyscrapers.
Outfitting historic buildings with such protections, on the other hand, can be tricky.
Fire detection and suppression equipment must be incorporated into the structure while maintaining its historic feel, said Devlin, who oversaw such a project at the U.S. Supreme Court in Washington and is now doing so at the New Jersey Statehouse in Trenton.
For some historic structures, a sprinkler system may be the wrong approach if the contents are vulnerable to water damage, he said.
Once again, churches present unique issues. Installing sprinklers at the top of a high, vaulted space is likely to be ineffective for two reasons: If a fire breaks out on the floor of a church, it may take too long for temperatures near the ceiling to rise high enough to activate sprinklers. And because a ceiling sprinkler would be located so high above the fire, the water could evaporate before it does any good.
“If the fire is large, the sprinkler droplets may not even be able to penetrate to the fire plume,” Devlin said.
In cases where sprinklers are not indicated, fire protection engineers resort to other strategies, such as firewalls to block the spread of a blaze and early smoke detection so that fires can be extinguished manually. Engineers also consult with the stewards of historic buildings on the judicious placement of any furniture and other objects that could fuel a blaze.
Secular structures also may lack adequate protection.
In the 1980s, the sprinkler system at Independence Hall had degraded to the point that some of its pipes could be crushed by hand, and in 1991, the building was featured in the National Trust for Historic Preservation’s list of top 11 endangered sites.
The National Park Service upgraded the fire-suppression system soon thereafter as part of a $17 million overhaul. It has spared the building from serious damage on at least one occasion, activating in January 2001 when a faulty transformer started a smoky blaze in a tunnel that connects the building with the adjacent Old City Hall.
At Christ Church, the original “water curtain” feature was installed in the 1920s, though it had stopped working well before the upgrade 15 years ago, said longtime member Bruce Gill, who serves on the church’s property committee. An internal sprinkler system was installed a few years after that.
Preservation advocates say it is unclear how many historic buildings lack adequate fire protection. But in Philadelphia alone, most of the 800-plus historic churches have not engaged a fire-protection engineer for a proper risk assessment, said Jaeger, of Partners for Sacred Places.
Such measures can be expensive. But not as expensive as the vast rebuilding that is in store for Notre Dame.
Outside Christ Church before the sprinkler demonstration Wednesday, the Rev. Tim Safford quoted a version of a statement attributed to one of the church’s most famous members, Benjamin Franklin:
"A penny of prevention is worth a pound of cure.”