Metro track walkers exit the tunnel at L'Enfant Plaza Metro Station on Jan. 13, the day after an incident where a Yellow Line train filled with smoke, leading to the death of one woman and forcing 80 passengers to seek medical attention. (Amanda Voisard/For the Washington Post)

In a recent test of radio equipment in Metro tunnels in Montgomery County, firefighters underground were unable to communicate clearly with emergency workers on the surface at some stations, a problem similar to one that hampered D.C. first responders last month during a fatal subway smoke incident near L’Enfant Plaza, officials said Sunday.

The problem in Montgomery was discovered during a routine bimonthly test of radio communication between firefighters in Red Line tunnels and others above the ground, according to an e-mail given to The Washington Post, dated Saturday and sent to personnel in the county’s Department of Fire and Rescue Service.

The test found that radio communication between tunnels and the surface at some locations was “poor to nonexistent,” according to the e-mail, sent by Battalion Chief Michael Baltrotsky, who oversees communications technology.

Baltrotsky’s e-mail did not specify how widespread the problem is. Metro spokesman Dan Stessel said Sunday night that Montgomery officials reported having problems near the Glenmont and Forest Glen stations and that the trouble was limited to those areas.

Until the problem is fixed, Baltrotsky wrote,“personnel will have little to no radio coverage in areas of the Metro system” during a public-safety crisis, “specifically in tunnels and some below-grade stations.”

Although radio-communication specialists in the Montgomery fire department and county government are working with Metro to “remedy the problems,” Baltrotsky wrote, “there is NO estimation on a time for complete repair.”

Northwest of Friendship Heights, on the Maryland-District border, there are seven Red Line stations in that part of Montgomery, and four at the line’s other end, from Silver Spring to Glenmont. The Red Line is the busiest of Metro’s six subway routes.

“I’m surprised that they came up with these problems,” Pete Piringer, a spokesman for Montgomery Fire and Rescue Service, said Sunday. “Up until this point, radio communications have been very good. In fact, they’ve been perfect, I’m told.”

The problems Baltrotsky described — possibly involving signal-relaying equipment that is built into the subway and maintained by Metro — echo the problems that D.C. firefighters encountered during the Jan. 12 crisis near the L’Enfant Plaza station.

After a southbound Yellow Line train stopped amid heavy tunnel smoke, caused by a electrical malfunction on the tracks, scores of choking passengers waited more than 30 minutes for help to arrive. One of them, Carol I. Glover, 61, of Alexandria, died of smoke inhalation, an autopsy found.

Amid the rescue effort, firefighters in the tunnel had trouble communicating by radio with commanders aboveground. Since then, Metro and the D.C. fire department have largely blamed each other for the problems, which they said have since been fixed.

Metro’s interim general manager, Jack Requa, told the transit agency’s board of directors that several days before the Jan. 12 incident, the D.C. fire department made technical changes to the way its radios work.

Because fire officials did not immediately alert Metro to the changes, Requa said, Metro did not make necessary changes to its underground signal-relaying equipment. As a result, firefighters’ radios did not work properly in the emergency.

In a published report on the incident, however, the District’s homeland security agency partly disputed Requa’s account, saying Metro equipment was at fault. Transit officials were “notified of the issue, but repairs were not made prior to the January 12 incident,” the report said.

In Montgomery, Piringer said, firefighters tested radio communication in Metro tunnels immediately after the Jan. 12 incident and found it working fine.

He said it isn’t clear why the system has broken down, although Baltrotsky’s e-mail refers to trouble involving “BDA coverage.” BDAs, Piringer said, are bi-directional amplifiers, which are built into the subway and used to relay radio signals.

“We share responsibility for making all this work,” Piringer said, referring to Metro and the Montgomery fire department. “But Metro is responsible for the hardware.”

Until the trouble is fixed, Baltrotsky wrote, “personnel are reminded to use radio relays to ensure complete communications when operating in below-grade environments.”

By “radio relays,” he meant that firefighters with radios should position themselves at key points from a tunnel to the surface — one firefighter within sight of another — so they can relay information back and forth, Piringer said.

He described what would amount to a verbal bucket brigade. “If you have to relay something up an escalator or around a corner, something like that, you have firefighters with radios all along the way, in line of sight,” Piringer said. With no obstaclesin the way, one radio would transmit adequately to another, he said.

“It’s easily accomplished,” Piringer said. “You just have to know how to do it.”