Over 100,000 varieties of face masks are currently on sale. They come in silk, cotton and synthetics; with and without filters; on the head and on the ears. They have sparks and sunflowers; friendly greetings and insults; cartoon characters and tiny reindeer.
What they don’t have is a label that shows how well they block infectious particles, an omission that has frustrated public health officials during the coronavirus pandemic. These experts note that there is a wide range of efficiency of various models, and some barely filter particles.
“The most basic and fundamental question is, what is the safest mask and how can I make sure I have it, and that my family members and my children have it?” said Fran Phillips, who resigned in August as Maryland’s assistant secretary of health. “It’s so surprising that we’re here right now and we don’t have this information.”
That could change soon. A division of the Centers for Disease Control and Prevention is working on developing minimum filter efficiency standards and labels indicating which products meet them, for the large and confusing market for masks and other face coverings.
The National Institute for Occupational Safety and Health, a division of the CDC known as NIOSH, quietly drafted guidelines with an industry standards organization, ASTM International (formerly the American Society for Testing and Materials), which are expected to be released next month.
“By having a standard in place, you will be able to know what level of protection is being achieved and you will have a consistent way of evaluating these products,” 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 masks. The Food and Drug Administration and the CDC have some authority over the industry. The FDA, which regulates medical devices, shares authority with NIOSH for the oversight of N95 respirators, which are 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.
Sales of masks took off after the FDA issued an emergency measure in April – as healthcare facilities struggled to obtain enough protective gear – which in part indicated the agency would not take action against the companies that sold them to the general public. At the same time, however, the FDA also noted that these products “may or may not achieve levels of fluid barrier or filtration efficiency.” This warning did not hurt the market, and some critics are now blaming the FDA for the poor quality of many products sold.
“There were a lot of things the FDA could have done to improve the situation, especially after research started to find out which masks worked and which didn’t,” said Diana Zuckerman, president of the National Center for Health Research. , a nonprofit health policy group. . “The FDA could have issued a directive that masks should be fitted, at least two layers of fabric, not made of stretch materials, etc.” Instead, there was a free-for-all. “
The effectiveness of masks can vary “from 0 to 80%, depending on the material composition, the number of coats and the bonding of the coats,” said Dale Pfriem, president of Protective Equipment Consulting Services and a member of the working group. for the development of standards dealing with mask guidelines.
The gold standard for masks is N95, which fits perfectly and can filter out at least 95% of very small particles. But N95 masks are generally only used by healthcare practitioners, and they have been rare since the start of the epidemic. Hospitals, desperate for more N95, have been led to a burgeoning black market to secure them.
To compensate for the shortage, the FDA authorized last spring the sale of KN95, the Chinese equivalent of the American N95. But the agency quickly detected fraudulent and counterfeit products and narrowed down the scope of authorized KN95 imports. Despite this, the agency recognizes that there is still rampant fraud, with countless companies dabbing “KN95” on masks that do not meet FDA standards.
A cut below the N95 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 that sell knockoffs, which do not offer the same level of protection.
And then there’s the Wild West: millions of masks fashioned from every possible fabric, from a single layer, as well as bandanas and gaiters, which are closed loops of fabric that are worn around the neck and can extend to cover the lower part. of the face.
Just about any mask is better than no mask, say public experts. The CDC has updated its mask guidelines on several occasions, noting that a tightly woven, multi-layered fabric provides better protection than a mask made of a single layer of fabric or loose knit – for the wearer and the people with whom the wearer comes into contact. But the agency’s website isn’t clear on whether masks with filters offer better protection than those without them, or how synthetic fabrics 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 how to use and care for them,” said Linsey Marr, professor of civil and environmental engineering at Virginia Tech. and leading expert on airborne viruses.
A task force made up of federal officials and industry has proposed a high filtration requirement and a low requirement that manufacturers and distributors can adopt and list on their labels. The lower standard is 20% filtration barrier and the higher is 50%.
These numbers are more protective than they appear. Filtration efficiency percentages are based on a product’s efficiency at filtering particles measuring 0.3 microns, which, as generally the most penetrating particles, are standard for NIOSH testing.
“A 20% efficiency at 0.3 microns would translate into a 50% efficiency for particles of one to two microns and an efficiency of 80% to block particles of four to five microns or more,” said Dr. Marr. “I think it will be useful.”
According to Dr Marr, the coronavirus itself is 0.1 microns in size, but it is carried in aerosols that can vary in size by about 0.5 microns.
Jeffrey Stull, a member who helps write the standards, said the group would also rate masks and face covers in terms of “breathability.” The standardization project, he said, has come a long way.
“It was a very difficult process,” said Mr. Stull, President of International Personnel Protection Inc. “We had a hard time finding that consensus on what the level of performance should be. We were originally talking about higher standards, and they said, “No, 80% of the industry can’t comply – it won’t do any good. So we had to balance that.
Manufacturers who wish to find that they meet the ASTM standard must first have their products tested by an accredited laboratory. They should also be able to show that their masks reasonably fit the general population. Those who do meet the standards can then find that they are meeting the ASTM standard on the product or packaging. However, there is no enforcement mechanism.
Daniel Carpenter, professor of government at Harvard, called NIOSH’s work to develop the standard “regulatory entrepreneurship.”
“He says, ‘Let’s use the tools that we have, even though we don’t have formal regulatory tools,” Carpenter said. “It’s another method of regulation. This can have a pretty big regulatory effect because if you don’t comply with the standards, you don’t get the seal of approval. “
Mr Pfriem hopes the standards will catch on. “What we have here is a very good standard,” he said. “Manufacturers will have something to design their products, and something to put in their marketing materials 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, which is made, for example, in your neighbor’s garage, will not be able to meet this standard.”