How effective is the mask you are wearing? Maybe you will know soon

There are currently more than 100,000 types of face masks for sale. They are available in silk, cotton and synthetic material; with filters and without; over the head and over the ears. They have glitter and sunflowers; best regards and insults; cartoon characters and teeny reindeer.

What they don’t have is a label showing how well they block infectious particles, an omission that has frustrated public health officials during the coronavirus pandemic. Those experts note that there is a wide range in the effectiveness of different designs, and some of them barely filter out particles.

“The most basic, basic question is, what is the safest mask and how can I make sure I have it and my family members and children have it?” said Fran Phillips, who stepped down from her position as Maryland’s deputy health secretary in August. “It’s so surprising that we’re here right now and don’t have that information.”

That could change soon. A division of the Centers for Disease Control and Prevention is developing minimum filter efficiency standards and labels that identify products that meet them for the vast and baffling market for masks and other face covers.

The National Institute for Occupational Safety and Health, a division of the CDC known as NIOSH, has been quietly writing guidelines with an industry-standard setting organization, ASTM International (formerly the American Society for Testing and Materials), which are expected to be made public next month made.

“By having a standard, you know what level of protection is being achieved and you can evaluate these products in a consistent manner,” said Maryann D’Alessandro, director of the NIOSH National Personal Protective Technology Laboratory.

Since the start of the pandemic, there has been little federal oversight of masks and other face covers. Both the Food and Drug Administration and the CDC have some authority over the industry. The FDA, which regulates medical devices, shares authority with NIOSH to oversee N95 respirators, the most protective devices available. But most masks worn by the general public are just pieces of cloth and are not subject to any regulatory oversight.

Mask sales boomed after the FDA issued an emergency measure in April – when healthcare facilities struggled to obtain adequate protective equipment – that said, in part, the agency would not take action against companies selling them to the general public . At the same time, however, the FDA also noted that these products “may or may not meet liquid barrier or filtration efficiency levels.” That warning didn’t hurt the market, and some critics now blame the FDA for the poor quality of many of the products being sold.

“There were many things the FDA could have done to improve the situation, especially after research revealed which masks worked and which didn’t,” said Diana Zuckerman, president of the National Center for Health Research, a nonprofit group for health research. health policy. . “FDA could have issued a guideline that masks should be applied, at least two layers of fabric, not made of stretchy materials, etc. Instead, there was one free for everyone.”

Mask effectiveness can range “from 0 percent to 80 percent, depending on material composition, number of coats, and layered adhesion,” said Dale Pfriem, president of Protective Equipment Consulting Services and member of the standards development working group on mask guidelines.

The gold standard for masks is the N95, which fits well and can filter at least 95 percent of very fine particles. But N95 masks are generally reserved for health professionals, and they have been scarce since the outbreak began. Hospitals, desperate for more N95s, have driven to a thriving black market to secure them.

To make up for the shortage, the FDA approved the sale of the KN95, the Chinese equivalent of the US N95, last spring. But the agency soon discovered fraudulent and counterfeit products and narrowed the range of allowed KN95 imports. Despite this, the agency acknowledges that fraud still persists, with numerous companies stamping “KN95” on masks that do not meet FDA standards.

One step below the N95s in terms of protection are FDA-approved surgical masks, which must meet certain agency standards. The style of the surgical mask is often copied by companies selling imitations, which do not offer the same level of protection.

And then there is the Wild West: millions of masks made of every possible fabric, from a few layers up, as well as bandanas and leggings, these are closed loops of fabric that are worn around the neck and can extend to cover the lower part. of the face.

Virtually any mask is better than no mask, public health experts say. The CDC has repeatedly updated its guidelines on masks, noting that a tightly woven, multi-layer fabric provides better protection than a mask made of a single layer of fabric or a loose fabric – for both the wearer and those with whom the wearer comes into contact . But the agency’s website does not clarify whether masks with filters provide better protection than masks without filters, nor how synthetics compare to cotton or other materials.

“There has been a critical need for some sort of national program to test and certify masks, and to communicate with people about the use and care of masks,” said Linsey Marr, professor of civil and environmental engineering at Virginia Tech and a leading expert on airborne viruses.

A working group of federal and industry officials has proposed one high and one low filter requirement that manufacturers and distributors can apply and list on their labels. The lower standard is 20 percent filtration barrier and the higher is 50 percent.

Those numbers are more protective than they sound. Filtration efficiency percentages are based on the efficiency of a product in filtering 0.3 micron particles, which, as the typically most penetrating particles, are standard for NIOSH testing.

“Twenty percent efficiency at 0.3 microns would translate to 50 percent efficiency at particles one to two microns, and 80 percent efficiency at blocking particles that are four to five microns or larger,” said Dr. Marr. “I think it will be useful.”

According to Dr. However, the coronavirus itself is 0.1 microns, but it is transported in aerosols that can range in size from about 0.5 microns.

Jeffrey Stull, a member who helps write the standards, said the group would also rate masks and face covers for “ breathability. ” The standard-setting project, he said, has been a long time.

“It has been a very difficult process,” said Mr. Stull, president of International Personnel Protection Inc. “We’ve struggled to find this consensus on what the level of performance should be. We were talking about higher levels originally, and they said, ‘No, 80 percent of the industry can’t meet this – that’s not going to do anyone any good. ‘ So we had to balance it. “

Manufacturers who wish to certify that they meet the ASTM standard must first have their products tested by an accredited laboratory. They must also be able to demonstrate that their masks are a reasonable fit for the general population. Those who do meet the standards can then notice on the product or packaging that they meet the ASTM standard. However, there is no enforcement mechanism.

Daniel Carpenter, a professor of government at Harvard, called NIOSH’s work in developing the standard “regulatory entrepreneurship.”

“It says, ‘Let’s use the tools we have, even if we don’t have formal regulatory tools,” said Mr. Carpenter. “It is an alternative way of regulation. It can have a pretty significant regulatory effect because if you don’t meet the standards, you won’t get approval. “

Mr. Pfriem hopes that the standards will catch on. “What we have here is really good standard,” he said. “Manufacturers will have something to design their products on, and something to put in their marketing collateral and packaging, and consumers will have a sense of confidence.”

He added, “I can tell you that a lot of what is marketed on eBay and other sites, manufactured in your neighbor’s garage, for example, will not meet this standard.”