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Last Updated

15 Feb 2003

Source: Washington Post, February 15, 2003

N95 Masks Flying Off Shelves, but They Offer Scant Protection

By Don Oldenburg, Washington Post Staff Writer

The latest hype and misinformation coming out of our latest Code Orange emergency preparedness is about a disposable dollar mask made with white cloth and an elastic strap the N95.

Sold at medical supply and hardware stores, they're the lightweight, nose-and-mouth respirators designed for medical settings and good for blocking allergens when mowing the lawn. Which begs the question: Can a mowing aid fend off a weapon of mass destruction? How effective would they be in a biological, chemical or nuclear attack?

"Not much, but better than nothing," says Victor Utgoff, a defense analyst at the Alexandria-based private Institute for Defense Analysis who has studied gas masks. "They generally protect you from getting particles into your lungs, paint chips and things like that."

Although anthrax spores and smallpox aren't paint chips, the masks do provide protection against bioterrorism, since the most likely used bacterium would be dispersed in particle form, Utgoff says. In fact, the anthrax mail attacks first spotlighted the N95, as office mailrooms scurried for protective gear.

The N95 is made by various manufacturers under different names, from MSA's "Affinity Foldable Respirator" to 3M's "Particulate Respirator." Look for "NIOSH N95" on the package; the "N95" is a government efficiency rating that means the mask blocks about 95 percent of particles that are 0.3 microns in size or larger.

The N95 rating meets the Centers for Disease Control and Prevention guidelines for protection against tuberculosis and anthrax spores, as well as the most foreseeable bioweaponry, which ranges in size from 1.0 to 5.0 microns. So the N95s are more than capable of preventing their inhalation.

Senate Majority Leader Bill Frist (R-Tenn.), a physician and public health expert, upped the masks' visibility even more recently when he advised that people keep a mask rated N95 or better on hand for each member of the family in his book "When Every Moment Counts."

Then came Code Orange.

"We've had so many people in here, it's not funny," says Gloria Stallworth, manager of In-Home Medical Supply in Alexandria, estimating that 20 customers came by Thursday to purchase N95s and, based on calls, even more were expected yesterday and today.

In-Home Medical is selling the cheapest 3M model of N95 masks individually, in one size only, for $2.75. Stallworth says many customers are looking for reassurance about what the mask will do.

"We don't give recommendations," she says, directing those customers to the manufacturer's phone number on the packaging. "People are very afraid. But most of them know it is a temporary fix."

But N95s are no fix if terrorists use chemicals, Utgoff says: "Against chemical attack and gas, worthless."

Patrick Breysse, an industrial hygienist at Johns Hopkins Bloomberg School of Public Health, says: "There are respirators that would protect you in those cases, but they are much more expensive and sophisticated."

Dirty bombs?

"If it's a dirty bomb with a lot of dust, the respirator would help," Breysse says. "It would stop you from inhaling those particles. But . . . you can also get exposed without inhaling anything."

Even in a biological attack, the masks have major shortcomings. Like fit.

"Does it have a nose piece like a metal clip you can bend over your nose? That's a better model because the big kicker here is getting a good fit," Utgoff says.

Bad fits are deadly. Contaminated air breathed from around the unfiltered edges instead of through the N95-rated material undermines the purpose of a mask.

And, got a beard? "Shave it," says Breysse, who recommends duct-taping the mask to your face to make a good fit.

"For you to take a respirator and put it on without any training or fitting probably wouldn't give you the protection you are expecting," says Ron Herring, general manager of the Safety Products Division at Pittsburgh-based MSA.

MSA, a safety gear manufacturer that has been making gas masks and other equipment since 1914 for the military and first responders, recently entered the civilian safety market with its MSA Safety Works do-it-yourself products sold at Home Depot and other stores.

Herring says public interest in respirators has spiked dramatically. Sales of N95 masks on Amazon.com aren't ranked, but sales of MSA's $179 civilian Gas Mask Hood, basically a getaway respirator, are: Last week, hood sales ranked about 11,000 on the list. Earlier this week, it was up to 4,600. Wednesday, it rose to 300, Thursday, 30, and yesterday it ranked 13.

Another huge shortcoming is that you don't know when to wear a mask. There are no reliable early warning signs that a biological agent has been released. No big air-raid warning horn goes off. News reports will be after the fact. "So here I am, I've got a mask, and I don't know when to use it," Utgoff says.

The solution? If there was a biological attack tomorrow, say, in Los Angeles, he says, he might start wearing a mask nonstop. "If you think there's a good chance of a biological weapons attack, wear it as much as you can," he says. "Do I? No! Because I don't think it's very likely."

Another problem is that the single-use masks don't last. "They are disposable because they deteriorate with sweat and wear and age," Breysse says.

He keeps N95 masks around the house for doing odd jobs. "If there were an event tomorrow, and I was in my home, I would seal my home as best I could," he says, "and if I had one of these masks, I would put it on. Because why not?"