Long-awaited test results on escape hoods purchased to protect lawmakers and staff from potential terrorist attacks showed the masks had better-than-expected capabilities in filtering out biological and chemical agents but pose some significant risks to those with respiratory conditions.

“We needed to see what the gap was between present technology and the level of proficiency we needed,” explained Richard Mepzler, director of the National Personal Protection Technology Laboratory, a division of the National Institute of Occupational Safety and Health. “Our finding was that the standard we were producing was within reach of current technology. That’s very good news.”

Congressional officials and representatives from other federal agencies were briefed early last month by NIOSH, a division of the Centers for Disease Control and Prevention, which conducted tests on three of the leading breathing devices — including the QuickMask 2000 — in order to develop standards for such equipment.

The devices are designed to give wearers 10 to 60 minutes of breathable air in the event of a chemical or biological attack. Last year the legislative branch bought more than 40,000 QuickMask 2000s at a cost of about $100 each.

The Pittsburgh lab tested the hoods against a broad range of industrial chemicals and biological and chemical agents, including sarin and mustard gas. The agents were chosen jointly with the Army, which had previously assessed the masks for use in a military setting, as the most likely terrorist threats.

The respirators in the hoods “provided an extremely broad range” of protection, Mepzler said. “That was a surprise to us,” given the lack of federal standards.

The tests also confirmed that the hoods themselves stood up to “live” warfare agents, meaning that the materials used to prevent unfiltered air from reaching the device’s wearer were strong enough to resist permeation.

One of the potential problems the tests unveiled was the difficulty test subjects had in breathing through the respirator.

“Low oxygen causes you to not think well and eventually could cause death if it were low enough,” Mepzler said, but quickly added: “We are not talking about that situation” under the circumstances in which the escape hoods would be used.

Mepzler added that high levels of carbon dioxide, caused by rebreathing expelled air, “could cause headaches and [feelings] of strangulation and make you want to remove the mask. The consequences of this start with a headache and lead to confusion and [could] go on long enough to cause death.”

After bringing in NIOSH, Air Force and other medical experts, Mepzler said their conclusion was that the levels of carbon dioxide and oxygen in the escape hood respirators were “not life threatening.”

But he conceded that some individuals are at higher risk than others when using the masks. “People who are asthmatic or people who are older might have concerns,” he said.

That finding was the subject of an internal Office of Compliance e-mail sent last month.

“The bottom line at the briefing appears to have been: The masks are the best we have at the moment, but they have a lot of problems, particularly with regard to their use by certain categories of persons with particular health problems. In some cases, these problems could be serious to even life-threatening. However, the hoods are much better than nothing,” the e-mail said. “Our modus operandi here is to keep the issues regarding these masks ‘inside the circle’ of responsible stakeholders, and to try to foster improvements in the training for the masks to address some of these user problems in the interim until better respirators begin to come on stream in about 6 months.”

Office of Compliance Director Bill Thompson sent the e-mail to others in his office. A copy of it was obtained by Roll Call from outside the agency.

“We don’t want to unnecessarily create any anxiety on the part of the people who would use the masks in an emergency,” Thompson said in explaining his comments, “because they are the best available at this point.”

A legislative branch entity, the Office of Compliance was created by Congress in 1995 to be the enforcer of the Congressional Accountability Act, which applied 11 workplace and safety laws to Congress and its agencies. As such, the office works with Capitol Hill to ensure its practices meet federal standards, including the types of respirators used by staff in an emergency.

Until NIOSH evaluated the masks, the only federal government testing done on the devices before Congress and a host of federal agencies spent millions of dollars to purchase tens of thousands of them was by the Army’s Soldier and Biological Chemical Command in Edgewood, Md. They had never been tested in an occupational setting for use by civilians.

An Office of Compliance report done more than a year ago on the devices’ capabilities was circulated widely within the federal government, and it became the principally cited review by both the legislative and executive branches prior to the NIOSH review, according to Thompson’s e-mail.

“They have drawbacks, and those drawbacks need to be addressed in the training process,” Thompson said of the masks. “They are a whole lot better than nothing, and they offer a significant level of protection.”

Capitol Police Chief Terrance Gainer said in an interview that his department has been in close contact with the Office of Compliance about updating the training process to reflect the new findings and to “discuss our mutual concern about whether there is going to be new and better products and when.”

Gainer said the NIOSH study “showed that there were some potential downsides, but in balance and in context, I do think we have an effective, good product,” which will get better “in time.”

Now that NIOSH standards are set, manufacturers will begin submitting their products, possibly with necessary improvements, for review and certification. Mepzler said that process would likely take about three months.

NIOSH has been approving breathing equipment since 1972, but until late 2001 the agency didn’t examine these types of breathing devices. Congress set up the National Personal Protection Technology Laboratory after the terrorist attacks to evaluate devices for emergency responders. “It’s something we’re proud of to say we developed this standard so quickly,” Mepzler said.

Gainer said his department will monitor the new or improved products coming online and determine whether “we replenish the stock we have or hold off until the next available.” There are funds left from the fiscal 2003 supplemental appropriations for “lifecycle” mask replacements. Each unused device has about a four-year life span, and Congress has appropriated money for their periodic replacement.

“I think the glass is more than three-quarters full, frankly,” Gainer said of the masks.