Months before a fatal crisis Jan. 12 in which noxious fumes enveloped a Metro train underground, the transit agency set out to improve its decade-old computerized process for handling smoke emergencies in tunnels, documents show. But the planned upgrades, meant to help Metro pinpoint the location of smoke and coordinate the work of ventilation fans, have not advanced beyond the paperwork stage.
The documents — prepared for a possible contract for new computer software for Metro’s train-control center in Landover, Md. — indicate that the agency knew its system for dealing with smoke in tunnels needed to be modernized. For a year, however, Metro moved at a less-than-urgent pace in trying to complete the improvements.
Then disaster struck.
Last week, in its first substantial disclosures about the Jan. 12 incident, the National Transportation Safety Board said the tunnel calamity, near the L’Enfant Plaza station, was exacerbated by Metro’s inability to quickly identify the origin point of the smoke. Metro then activated two sets of tunnel ventilation fans at cross-purposes, pulling the smoke toward the train instead of pushing it away, the NTSB said.
Metro has been aware for months that its Landover train controllers are not adequately served by computer software that dates to 2002, even with modifications made in the past decade, the documents show.
A complete software replacement is needed to “make the rail system safer for customers and employees [and to] provide improved customer satisfaction through more reliable and efficient operation,” according to the documents. Called a “request for information,” the paperwork was prepared in January 2014 and made available to companies so Metro could start a dialogue with potential vendors about software products.
Metro hopes that the years-long process of overhauling the software eventually will make it easier for train controllers to perform a variety of tasks — particularly in emergencies. According to the documents, Metro wants its computer system to provide information that is “updated from real time, real world data” with “a very high level of accuracy [and] detail availability.”
If Metro proceeds with the project, its next steps will be drafting specifications for what it wants to buy and issuing a request for contract bids. To date, the replacement effort has not gone beyond the information-gathering stage.
In the Jan. 12 incident, scores of passengers were left gasping for air, with many sickened, after they were caught on a six-car Yellow Line train that stopped in a smoke-filled tunnel just south of the L’Enfant Plaza station. One woman died, and an autopsy found smoke inhalation to be the cause. Because of the ongoing NTSB investigation, Metro has said it is barred by federal regulations from commenting in detail on the incident.
As for any software overhaul, Metro spokesman Dan Stessel would say only that all aspects of the train-control center are under review.
The software modernization that Metro envisionsdovetails with “urgent recommendations” that the NTSB’s acting chairman, Christopher A. Hart, issued last week concerning Metro’s procedures for dealing with smoke in tunnels.
The recommendations, along with a letter Hart sent to Metro, offered new details about the Jan. 12 incident. Those details, combined with earlier information from officials and witnesses, create a clearer picture of what went wrong.
The origin of the crisis was a malfunction involving a bundle of power cables attached to the electrified third rail in the tunnel, the NTSB has said.
Although the malfunction apparently did not spark a major fire, it produced tremendous heat, causing melting and a large amount of smoke in a spot about 1,950 feet south of the L’Enfant Plaza station.
About 24 feet past that site, a ventilation shaft rises six stories from the tracks to the street. Because the spacious concrete shaft doubles as an emergency evacuation route, it has flights of metal stairs leading to the surface.
At the top of the shaft are four ventilation fans, each five feet wide. In “exhaust mode,” with the blades spinning counterclockwise, the fans can pull a total of 200,000 cubic feet of foul air out of the tunnel every minute. In “supply mode,” with the blades turning clockwise, they can push in fresh air at a rate of 140,000 cubic feet per minute.
Back at the station, two more big fans are installed beneath the passenger platforms. Together, depending on whether they are running in supply or exhaust mode, they are capable of forcing in 42,000 cubic feet of good air every minute or expelling bad air at a rate of 60,000 cubic feet per minute.
All 46 subterranean Metro stations have underplatform fans. And there are 85 fan shafts of varying depths in the subway’s 51.5 miles of tunnels. The fans are usually idle, Metro said. Except for emergencies, their main purpose is to clear tunnels of diesel fumes spewed by heavy equipment during track maintenance.
In what apparently was the first indication of trouble Jan. 12, a tunnel smoke detector near the L’Enfant Plaza station activated at 3:04 p.m., Hart said. Yet Metro train controllers, evidently unable to pinpoint the origin of the smoke, did not halt train traffic.
Train No. 302 headed south with more than 200 passengers, departing L’Enfant Plaza at 3:14 p.m. A minute later, the train encountered smoke and stopped, with its front car 836 feet beyond the station. Much more smoke was ahead.
The train operator notified the Landover center that he had run into smoke. Under Metro rules at the time, he had to await permission from controllers before turning off the train’s air-intake system, which by then was sucking smoke into the six cars. Whether the operator failed to ask for permission or did not receive it is not clear. In any case, the intake “was not shut off,” Hart said.
In addition to inhaling smoke that was seeping into the stationary cars through small openings, passengers were choking on vapor pulled in by the train’s “environmental system.”
Nine days later, on Jan. 21, Metro changed the rule. Train operators now are allowed to turn off air-intake systems in smoke emergencies without waiting for permission.
Also under Metro procedures, in a situation such as the one at L’Enfant Plaza, the train is supposed to return to the station. Passengers said the operator seemed to be desperately trying to move No. 302. They said the train lurched a few times but stayed put.
At 3:16 p.m., Hart said, the Landover control center switched on the fans under the L’Enfant platforms in exhaust mode, which meant that the fans were drawing the smoke toward the station — and toward the train — from deep in the tunnel.
About the same time, a mechanical engineer named Bill Bundens was driving along Maine Avenue SW, near the Wharf, a retail and residential construction project. Glancing left, Bundens, one of the project managers, noticed smoke pouring from the ventilation shaft, at Ninth and Water streets.
“I would never expect to see smoke coming out of a Metro vent,” said Bundens, 48, who parked his pickup truck and got out for a closer look.
Then he dialed 911.
It was 3:18 p.m.
“I know what it is because it’s on the project site,” Bundens said. “. . . We’re required to keep it clear in case of an incident.”
“You know, in case people need to come up that stairwell and exit,” he said.
As Bundens stood over the grate, at 3:24 p.m., the giant fans in the shaft roared to life. But those fans, like the two under the platform, were activated in exhaust mode. This meant that the two sets of fans, on opposite ends of the train, both were pulling the smoke. One set should have been pushing in fresh air while the other set expelled the smoke, Hart said.
Because the fans were not coordinated to create air circulation in the tunnel, the platform fans sucked the smoke toward the train while the shaft fans, pulling from the other direction, helped cause the smoke to settle over the train.The stranded passengers waited more than 30 minutes for rescuers to arrive and lead them back to the station on foot.
When D.C. firefighters reached the rail cars, Lt. Stephen Kuhn recalled, fumes were so thick that “we could not see its taillights until we were right next to the train.”
Besides warning that Metro “does not have the means to determine the exact location of a source of smoke in their tunnel network,” Hart voiced concern about whether subways in other cities are fully prepared for such crises.
In his “urgent recommendations,” Hart called for “a nationwide audit of transit agencies” by the Federal Transit Administration “to assess the state of tunnel ventilation systems, written emergency procedures for fire and smoke events, and training to ensure compliance with these procedures.”
Responding to Hart, the FTA’s acting administrator, Therese W. McMillan, said in a statement Thursday, “We are evaluating to determine the time and resources necessary to complete such an audit.”
Experts on dealing with smoke in subway tunnels say it would be impractical to draft highly specific guidelines, because every subway is different in terms of age, layout, infrastructure and other factors.
Two documents cited by an FTA spokesman as “best practices” spell out broad principles — including that transit agencies should have processes for precisely identifying the location of a “smoke event” and for coordinating the work of fans to keep fumes away from passengers. The documents come from the National Fire Protection Association and the American Public Transportation Association.
Procedures should be in place “with regard to the strategy for smoke management, who operates fans, when to activate fans, and how to operate the fans,” according to the APTA’s guidelines.
In calling for a nationwide audit by the FTA, Hart said some subways, such as San Francisco’s, “have developed detailed ventilation procedures for addressing train fires and smoke events in tunnels.” But Metro is lacking, he said. Although the agency’s safety manual “contains a number of key actions that must be taken when a train encounters smoke in a tunnel,” it “does not address tunnel ventilation strategies.”
As for Metro’s software overhaul, the floated plan shows Metro wants to divide the rail system into clearly defined zones so that when a smoke emergency arises, the Landover controllers, using the computer system, can quickly identify the origin point.
The software also would simplify their work in a crisis. Metro wants preprogrammed settings for its fans. Once the source of smoke is located and the fans have been turned on, the fans would automatically work in coordination.
The new software also would indicate to controllers whether any aspect of the ventilation system has malfunctioned in an emergency. On Jan. 12, Hart said, two of the four fans in the shaft “tripped an overload circuit breaker and were non-operational.”
At Ninth and Water streets, after Bundens dialed 911, he noticed that the flow of smoke from the shaft began to taper off.
Meanwhile, in the smoke-enveloped train, Navy pilot Jeffrey Todd, 43, endured the fumes for close to 30 minutes, he said, before he decided to bail out. “Walking through the tunnel seemed logically the safer course of action,” he recalled.
Todd said he used an emergency lever to open a car door. He stepped out and onto a narrow catwalk on a side of the tunnel. The smoke had originated ahead of the train. Yet the air seemed clearer in that direction than it did around him and behind, where the station fans were at work, pulling the fumes.
So Todd and a passenger whom he had just met, a man he would identify only as “John,” headed south on foot, farther into the tunnel.
The smoke “significantly reduced after I’d moved about 50 yards,” Todd said. He was walking in a crouch, staying below the remaining smoke, with the neck of his T-shirt pulled up from under his uniform top to cover his mouth.
After 100 yards, Todd stood upright. “The smoke was nearly cleared,” he said.
It was shortly before 4 p.m., by his reckoning, when he and his companion saw a large opening on the left side of the tunnel and light filtering down through a staircase. This was the ventilation shaft.
The heat-related damage to the third rail and other parts of the tunnel had occurred only 24 feet from the shaft. But there were minimal fumes, Todd said.
By that time, most of the smoke was back around the train and the station.
The two men ascended the stairs in the shaft, six stories to daylight. Soon they saw the bottoms of the boots of the firefighters summoned by Bundens.