Big Dig fire exits blocked
Work to fix leaks shuts escape routes
Editor's note: A Page One story and accompanying headline in yesterday's Globe about blocked fire exits in the Big Dig tunnels incorrectly said that many had been boarded up or blocked because of work to find and plug leaks in the tunnels. That assertion was not attributed to anyone or supported by other reporting, a breach of the Globe's standards. The exits are boarded up because they lead to areas of the Big Dig that are still under construction, according to Big Dig officials. In addition, the story incorrectly said the exits are the main escape route for motorists if a fire starts inside the tunnels. Big Dig officials say the primary evacuation route is for motorists to go back the way they entered the tunnels.
Numerous fire exit doors in the Big Dig tunnels are either boarded up or missing, and many fire exits are blocked, because of work to find and plug the hundreds of leaks in tunnel walls, a Globe survey found yesterday.
The steel doors, which are meant to stop flames and smoke for at least two hours, are the main escape routes for motorists if a fire starts inside the Interstate 93 tunnels. The problem is more visible in the northbound tunnel, where one exit, its sign still intact, was boarded over with painted plywood.
Fire Commissioner Paul A. Christian said yesterday that although he is concerned that fire exits are blocked and fire doors missing, Big Dig officials do not need to replace them immediately because the $14.6 billion project remains under construction.
The Fire Department's approval was the last hurdle before the tunnels could open to traffic, and that approval required all fire doors to be in place. The department approved the northbound tunnel in March 2003 and the southbound later that same year. The tunnels handle more than 200,000 vehicles a day.
Asked why that requirement isn't being enforced now, Christian replied: ''I'm not going to shut the tunnels down."
''It is the position of the Boston Fire Department that these fire doors were not pivotal for the fire safety of that tunnel," Christian added. ''And now that these problems have developed while the tunnel is operational, we can live with the conditions. It's not sufficient to warrant closing down the tunnel."
He said the doors must all be replaced and in working order by the time the project is complete in September.
Big Dig officials said they remain confident the tunnels are safe.
Project spokesman Doug Hanchett said the tunnels exceed federal standards for emergency exits and that no operational emergency exits have been boarded up due to repair work.
''Those that are barricaded are not yet in use due to unfinished work at the surface," he responded in an e-mail. He said that there are about six emergency exits not in use throughout the 8,000 feet of tunnel and that they are known to fire officials and are not shown on current emergency response plans.
Big Dig officials said some of those blocked exits are located near a future northbound on-ramp from South Street, the last piece of tunnel to be constructed, and won't be permanent exits.
''To my knowledge, all the exits are properly marked, and fire doors are intact," project director Michael P. Lewis said yesterday.
Christian also said he is worried about fireproofing falling from the southbound tunnel ceiling, saying he plans to force the Turnpike Authority to replace the material if it isn't done soon. He also said the leaks had compromised one of the tunnel's fire safety alarms several months ago, but it was quickly fixed.
Since the tunnels began leaking in January 2004, probes and repairs have altered the tunnels' structure and in some instances crippled some of the fire doors, which are designed to close automatically behind fleeing motorists.
The exits lead from the roadway to stairs that rise as high as five stories, or 120 feet, to the surface. Others connect to walkways in adjacent tunnels.
''That is a very important aspect of the fire protection for egress from tunnels in general and the Big Dig in particular," said Robert Zalosh, professor of fire protection engineering at Worcester Polytechnic Institute, who worked on the fire detection systems in the Big Dig.
''It is important to try to maintain those," he said.
In a tunnel fire, he said, the main threat is smoke. Although the Big Dig's ventilation system has been shown to remove smoke, people still have to get out, he said.
''It's important to make sure that any defect with fire doors should be minimized," Zalosh said. ''If smoke got into a stairway, it could be an issue."
In its short life, the Big Dig has had problems with fire. Last May, high-tech heat sensors in the Ted Williams Tunnel failed to detect a fire on the Seattle Mariners team bus until after it was nearly extinguished.
The fire caused a miles-long traffic jam and forced the 1.4-mile tunnel to close in both directions for several hours.
However, the turnpike's emergency response and the tunnel's ventilation system worked well, officials said.
The National Fire Protection Association's 2004 standards for road tunnels, a document created with major input from officials from Big Dig contractor Bechtel/Parsons Brinckerhoff and the Boston Fire Department, recommends that fire exits covered with automatically closing fire doors be placed every 1,000 feet in any tunnel the size of the Big Dig.
The standards were created as the Big Dig was being built, and with the megaproject largely in mind, after two catastrophic tunnel fires in Europe. In 1999, a fire inside the Mont Blanc Tunnel connecting France and Italy killed 39 people.
That tunnel had only small nooks in the walls for people to escape the flames, not exits.
With the Big Dig's current condition, especially the northbound tunnel, Boston fire officials said the fire safety standards are not being met.
Art Cote, executive vice president of the National Fire Protection Association in Quincy, said the standards are voluntary unless adopted by a state or agency. Neither the Turnpike Authority, which oversees the Big Dig, nor the Commonwealth have adopted the standards.
The Fire Department remains the only agency overseeing fire safety in the tunnel.
Katie Ford, spokeswoman for the Executive Office of Public Safety, said that other than some preliminary oversight during the tunnels' construction, the state has no control over Big Dig fire safety.
Christian said commuters should not worry about a deadly fire because trucks carrying hazardous materials aren't allowed inside the tunnels, reducing the chances of a catastrophic explosion.
''I'm certainly responsible for the safety of people in this city, and I don't think that the risk is to such a degree that it poses a health safety risk," he said. ''I use the tunnel myself."
Mac Daniel can be reached at email@example.com.