4

Developing Standards for PPE/PPT Design

Key Messages from Individual Speakers¹

• There is a gap in standards for ensembles of PPE—goggles, a respirator, a gown, and gloves, for example—and for the interoperability of the equipment and its functionality. (Holm)
• NIOSH could adopt and implement a fit performance requirement that addresses filtering facepiece respirators. (Tredinnick)
• A globalized set of standards would reduce confusion among end users and allow them to make clear comparisons of technologies and products to make the best decision for them and their application. Such standards would also make it easier for manufacturers to more quickly design products and get them to the people who need them the most. (Worple)
• NIOSH’s performance-based standards for respirators, rather than design-based standards, allow manufacturers to address the diversity of the U.S. population in terms of size and comfort and particular applications. (Schneider, Tredinnick)
• A regulatory framework for public health respirators would benefit the public, including children, and could be accomplished by

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¹ The following list of key messages is the rapporteurs’ summary of points made by the individual speakers identified, and the statements have not been endorsed or verified by the National Academies of Sciences, Engineering, and Medicine. They are not intended to reflect a consensus among workshop participants.

extending the current and effective NIOSH Respirator Approval Program. (Tredinnick)

• Designers responded to the public’s demand for PPE with a massive iteration of open-source designs that hospitals and university medical systems produced and that reached high levels of certification. (Jaqua)
• A focus on validating open-source designs would also give communities that have trouble procuring PPE access to designs that they know will provide them with high-quality PPE and save steps in the manufacturing process, resulting in communities getting the PPE they need more quickly. (Jaqua)
• Most doctors do not know the details of PPE and do not know how to find help for their patients with disabilities. Supporting and expanding this capacity would make a measurable difference in impact beyond single individuals. (Schneider)
• A major problem with anthropometric databases, which can enable the design of products that fit a broader range of individuals, is that they have poor representation of people of color and children. (Sokolowski)

The workshop featured a series of sessions aimed at discussing personal protective equipment (PPE) and personal protective technology (PPT) standards around specific components of the supply chain. In the first session of this series, the participants examined the standards relating to the design and manufacturing of PPE and PPT. To open the session, moderator Stephanie Holm, director of the Western States Pediatric Environmental Health Specialty Unit at University of California, San Francisco, and public health medical officer in the Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, said that the Product Standardization Task Force² identified several standards gaps that affect the design of PPE and PPT. For respirators, for example, there are no requirements to assess outward leakage or source control, so requirements for this assessment could affect how respirators are designed. There is also no standard for respirator use among pediatric users, and such a standard would have notable implications for PPE design, said Holm.

For eye and face protection devices, there are gaps regarding protection from aerosols and in offering guidance for addressing fogging, for example. In addition, there is a gap in standards for ensembles of PPE—goggles, a respirator, a gown, and gloves, for example—and for the interoperability of the equipment and its functionality.

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² Additional information is available at https://aspr.hhs.gov/newsroom/Pages/SupplyChain-9Mar2022.aspx (accessed May 2, 2023).

HOW STANDARDS INFLUENCE PRODUCT DEVELOPMENT AND SUPPLY

Joe Worple, senior design engineer at Milwaukee Tool, explained that his work focuses on providing innovative solutions for PPE products for job sites. The company’s core trade users were all essential workers during the COVID-19 pandemic, and as a result, the company launched more PPE products during the pandemic than at any other time in the company’s history.

Looking at individual standards and the ability to innovate within them, Worple called for attention to design requirements versus performance requirements. For example, the standard for rubber-insulated gloves for utility workers defines what the glove looks like, its composition, the material selection from Dow Chemical, mechanical properties, and material thickness. However, user feedback has revealed these bulky gloves make it difficult to do intricate and delicate work. As a result, there would appear to be an opportunity to innovate and design gloves that are more dexterous and breathable. “But the current standards do not allow for that, which makes it hard for us to please our end users and ultimately make them safer on the job site,” said Worple. One way to get around this obstacle, Worple mentioned, is to have more robust performance requirements and performance targets rather than design requirements with strict dictates.

Worple then turned to the subject of global harmonization of PPE standards, how to expedite time-to-market for many products and how to eliminate confusion on the job site and with end-user groups regarding which product is safer and meets their needs. Looking across the world, he said, job sites are relatively similar to one another and come with similar hazards. However, there are different standards for industrial head protection, for example, each with its own product design and performance requirements (ANSI and ISEA, 2014; CSA Group, 2015; Dansk Standard, 2003; DIN, 2006).^3,4 A globalized set of standards, said Worple, would reduce confusion among end users and allow them to make clear comparisons between technologies and products to make the best decision for them and their application.

Worple stated the globally standardized requirements would also make it easier for manufacturers to more quickly design products and get them to the people who need them the most. Typically, designing a product at Worple’s company takes 6 to 18 months. For head protection, that means one design for a U.S. helmet, one for a Canadian helmet, and

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³ Personal Protective and Life Saving Equipment, 29 CFR § 1926.100 (July 1, 2013).

⁴ Protective Clothing, 30 CFR § 77.1710 (December 30, 1969).

a third for a European helmet. His company, with 25 design engineers, can handle that challenge and dedicate the necessary resources, but the multiple requirements can prohibit smaller companies from entering new spaces that need innovative solutions for different PPE products. “I think harmonizing global standards would go a long way in leveling the playing field and getting PPE out to the ones who need it most,” said Worple.

THE IMPACT OF STANDARDS ON THE DESIGN OF RESPIRATORY PROTECTION AND SUPPLY CHAIN RESILIENCE

Jessica Tredinnick, manager of Global Standards Development for 3M Personal Safety Division, pointed out that with standards that affect PPE, and respiratory protection in particular, many problems have been solved. For example, it is 3M’s view that the existing standards respirators must meet as part of the National Institute for Occupational Safety and Health’s (NIOSH’s) approval program are optimally flexible to help ensure that respirators can deliver the protective performance needed. Those standards specify the performance criteria needed to confirm respiratory protection effectiveness without dictating how that effectiveness needs to be accomplished via respirator design. NIOSH’s performance standards approach allows manufacturers to address the diversity of the U.S. population in terms of size and comfort and for particular applications.

Creating and applying unnecessary standards, and in particular overly prescriptive design standards, would stifle innovation and could reduce the quality of products that are available while also stifling competition, said Tredinnick. Creating overly specialized PPE designs and design standards for specific applications will reduce manufacturers’ ability to scale up quickly by flex-purposing production capacity of high-volume general industry PPE, which enabled manufacturers such as 3M to respond to spikes in demand during the COVID-19 pandemic. “I want to encourage all of us to not overengineer a standardization solution because it might end up exacerbating some of the supply chain challenges that we have been talking about today,” said Tredinnick.

Nonetheless, there are gaps in U.S. respiratory protection standards to address improved supply chain robustness for health care and to position the United States for success in developing a regulatory framework that also addresses public health respiratory protection, said Tredinnick. As for the design of filtering facepiece respirators, including N95^®5 respira-

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⁵ N95 is a certification mark of the U.S. Department of Health and Human Services (HHS) and is registered in the United States and several international jurisdictions.

tors, she suggested that NIOSH could adopt and implement a fit performance requirement that addresses filtering facepiece respirators (FFRs). She noted that during the COVID-19 pandemic, many of the company’s health care customers reported that they were receiving N95 respirators from the Strategic National Stockpile (SNS) that did not fit enough of their workforce to be useful for them. Rather than a sizing issue, this was the result of limited availability of respirators that could accommodate the diverse shapes of workers’ faces and heads. Toward that end, Tredinnick voiced her support for NIOSH’s intention in 2023 to propose a rule on respirator fit capability that would apply to FFRs.

A second gap Tredinnick highlighted was the lack of a regulatory framework for respirators intended for public use. She noted that 3M has designed, manufactured, and sold respirators for children in other countries where the scope of respirator approval programs is broader and they support approval of products for nonworker populations, including children. In these frameworks, the manufacturer specifies the face size range for which a product is designed and then demonstrates via testing to a performance standard that the respirator design adequately fits those face sizes.

The United States, said Tredinnick, could extend the current, effective NIOSH Respirator Approval Program to include public health respirators. N95 respirators, she said, can and do work for members of the public, and the more similar that respirators for the public are to N95 respirators approved for use in occupational settings, the more adaptable and robust the supply chain will be. However, to inform which small adjustments might be needed for public health respirator designs, public health guidance would be helpful to describe when and where to use the respirators and for a better collective understanding of what level of inhalation protection is needed for members of the public. “The reason this is needed is because the design process for any respirator involves navigating the balance of many design considerations, including the sealing ability of the design and the comfort of the design,” said Tredinnick.

For workplace applications, the selection framework set by the Occupational Safety and Health Administration (OSHA) sets clear expectations for the quality of the needed fit and advises that respirator designs balance market expectations for sealing performance with end-user expectations for comfort. “That is true in any occupational population and is also true in public health populations,” said Tredinnick. An appropriately flexible respirator fit performance standard could then specify a fit performance requirement for specific portions of the U.S. population, such as adult or child members of the public. This specification would enable manufacturers to innovate designs that optimally balance effective sealing or protection capability with the comfort and other desired accommodations, she said in closing.

EXPLORING OPEN-SOURCE DESIGN OF PPE TO INCREASE EQUITABLE PUBLIC ACCESS

Victoria Jaqua, medical community lead for Open Source Medical Supplies (OSMS), explained that her organization is a grassroots advocacy group that encourages the creation and manufacture of open-source designs⁶ to get PPE into hospitals and to the public quickly. She noted that during the COVID-19 pandemic, creators of PPE brought PPE designs to hospitals and university medical systems that would test the equipment through their clinical staff or their infectious disease departments. If it held up to the hospitals’ internal standards, the PPE was often used by both staff and members of the local communities. Jaqua asked the participants “to remember that health care workers are also members of the public,” and since many are used to being protected by high-quality PPE standards at work, there is the expectation that equally high standards be applied to PPE intended for public use. This was especially true, she added, when people were under quarantine and when parents were taking care of sick children. Designers whose open-source PPE designs met the needs of specific health care facilities now have their designs housed in OSMS’s project library for anyone to access.

Today, the existing regulatory pathways for medical device manufacturing are mainly based on a performance-validation for individual manufacturers. However, said Jaqua, more focus on validating open-source designs and encouraging the innovation that occurs through that pathway would enable development of software packages for open-source designs. If open-sourced designs for PPE could be validated and made publicly available, and the PPE manufactured to specifications, Jaqua said, this could increase supply chain resiliency while providing the public with equipment that would be safe to use.

A focus on validating open-source designs would also allow communities that have trouble procuring PPE in a timely manner to access designs they know will provide them with high-quality PPE, said Jaqua. This would also save steps in the manufacturing process, which would result in communities getting the PPE they need more quickly.

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⁶ A design artifact (blueprint, software, code) that is published under an open source license, and is made available on a publicly-available platform in the form of source files that can be modified freely (https://pubsonline.informs.org/doi/10.1287/orsc.2013.0872 [accessed May 2, 2023]).

INNOVATIVE PPE DESIGNS TO MEET THE NEEDS OF A DIVERSE POPULATION⁷

Jennifer Schneider, professor and Eugene H. Fram Chair of Applied Critical Thinking in Academic Affairs at the Rochester Institute of Technology, noted that people come in all shapes, sizes, and abilities, and that according to the Census Bureau, there are some 26,500,000 nonelderly disabled people in the United States. She said that when the pandemic hit, her institution needed respiratory protection for thousands of abled, disabled, and hearing-impaired faculty, staff, and students, including those at the National Technical Institute for the Deaf.

Schneider explained that clear masks for respiratory protection are not just for deaf and hard-of-hearing individuals but also for those around them. “To participate in society, seeing faces is critically important, and it is not just the 12 million hearing-impaired but many with communication challenges and processing challenges that need faces, and it sure helps the rest of us, too,” said Schneider. “We did not know how much we relied on faces until we could not see them.”

In response, the Rochester Institute of Technology created a clear mask project with engineers, physicists, industrial designers, textile experts, material scientists, interpreters, and the deaf and hard-of-hearing community on campus. This project evaluated the product marketplace and worked to design and identify solutions for respirator users who also use hearing aids, cochlear implants, glasses, and other accessibility aids. Most of the products tested did not stand up to normal use or provide visibility. “We need a capability for filtration, ease, dexterity, and adjustability,” said Schneider. “We also need to consider how to manage [the Americans with Disability Act] and disabled education plans while providing safety for the disabled and those around them.”

In addition, said Schneider, there is a lack of appropriate testing protocols. Accessibility, she said, is governed by usability, and usability depends on the capacity of the users, their relationship to the hazard—different users experience hazards differently—and additional constraints such as other physical conditions, fit needs, and ear clearance with hearing aids. Accessibility, she added, is not providing equity if someone with a disability is present; rather it is expecting all types of persons to be pres-

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⁷ Topics discussed in this section were the focus of a 2021 Federal Register Notice (FRN) issued by NIOSH requesting information on the needs of U.S. worker populations who are underserved related to PPE use, availability, accessibility, acceptability, or knowledge. https://www.federalregister.gov/documents/2021/06/24/2021-13263/needs-and-challenges-in-personal-protective-equipment-ppe-use-for-underserved-user-populations (accessed May 23, 2023).

ent and participate. Importantly, inclusive actions benefit more than the disabled—they make things better for everyone.

Schneider suggested broadly orienting standards as performance-based wherever possible, for this provides flexibility for makers and users. She also suggested getting as much feedback as possible from PPE users. Her final suggestion for making inclusive PPE was to fund centers that can create and guide the production of PPE for special user communities, particularly for applications not easily commercialized, and to use the results to guide standards for broader use.

Unfortunately, she said her experiences and those of her colleagues at her institution have been that most doctors do not know the details of PPE and do not know how to find help for their differently abled patients. “Supporting and expanding this capacity would make a measurable difference in impact beyond single individuals,” said Schneider.

Susan Sokolowski, professor and founding director of the Sports Product Design Program at the University of Oregon, explained that her work focuses on anthropometry, the systematic measurement of the human body. Originally used by physical anthropologists, anthropometry is now used across academic fields to understand anatomical variation in size and shape. Her work uses three-dimensional scanning technology to capture the human form to develop blueprints for product design, particularly equitable PPE solutions for women and individuals from minority communities.

As an example of how her work is addressing gaps related to PPE design to influence future standards, she cited studies showing that N95 respirator fit-pass rates differed by sex and ethnicity. For instance, Caucasian males and females have, on average, higher fit-pass rates compared to Asian males and females, at 90 percent and 84 percent, respectively (Regli and von Ungern-Sternberg, 2020; Regli et al., 2021). Further stratification shows that for Asian females, the fit-pass rate was only 60 percent.

In her work, Sokolowski has found three major challenges that prevent designers and developers from creating equitable N95 respirators. The first is that the majority of the large scanning databases are incomplete for people of color. This means that some scanners cannot capture all the physical details from people of color, making it difficult to collect accurate measurements (Sokolowski et al., 2021). “We see similar results for foot data, calling out the need for scanning companies to validate their technologies for all skin colors,” said Sokolowski.

The second challenge is that scanning databases often collect head scans from people wearing skull caps that cover their ears. Given that the ears are a major anchoring point for the design and fit of a respirator, data collectors could do a better job of capturing better scan data, said Sokolowski. The third challenge she described is that the software that

converts images to create what she called watertight models turns the faces of people of color into White faces.

A second example focused on glove design, and in this study, Sokolowski and her collaborators assessed glove fit for more than 700 subjects at the Minnesota State Fair (Sokolowski et al., 2020). This work inspired the research team to develop a new set of anthropometric measures for glove design with 22 measures, as opposed to the standard 5 measures that most anthropometric studies have used for PPE development.

In a third example, Sokolowski discussed work related to coat, pants, glove, and boot sizing, and the fit challenges female fire fighters describe (Sokolowski et al., 2022). In this work, she and her colleagues identified several challenges resulting from firefighting PPE not being sized and fitted with enough body measures, including those of the circumference and length of the body. National Fire Protection Association (NFPA) standards only call out four measures when sizing and fitting PPE, none of which include hip and major measures between the chest and waist and waist and hip. “For women and minorities, these are where the problems lie in fit and sizing,” she said, noting the opportunity to improve standards that would improve the fit and safety for all firefighters.

DISCUSSION

To start the discussion, session moderator Holm asked Schneider if a national pediatric medical group could write standards for pediatric respirators, noting that as a pediatrician herself, she received no training on respirators or respiratory protection. Schneider replied that pediatricians would be a welcome part of this process because they understand the constituency better than a certified industrial hygienist, for example, but including them would require partnership between pediatricians and industrial hygienists.

Holm then asked Sokolowski if the data she presented is available publicly and if there is a place where people can find fit data for face masks and respirators for White versus Asian people, for example, and for other racial and ethnic groups. Sokolowski said that a major problem with anthropometric databases is that they have poor representation of people of color. Of the main databases that she frequently uses, one (the U.S. Army Natick Database) has more comprehensive data on people of color but since the data are generated from military personnel, the age ranges and body types represented differ from common PPE users, so this database also has limitations. She noted that one of her colleagues, Lindsey Griffin at the University of Minnesota, is creating a face scan database that includes children’s face scans and anthropometric data. Sokolowski added that one reason children’s data are missing in most databases is

that capturing data from children is often difficult under university institutional review board regulations designed to protect children. Nicholas Smit, former executive director of the American Medical Manufacturers Association (formally the American Mask Manufacturers Association), added that some countries do have masks standards for children, and those countries could guide U.S. efforts to develop standards for children.

Jaqua responded to a question about how OSMS tests PPE. The answer, she said, is that it does not do testing—that is done by university systems, physicians, engineers, and others. Her organization simply serves as a library for more than 200 open-source designs of PPE.

When asked how standards might help with design strategies that would decrease confusion as to what types of PPE are suitable for different settings, Jaqua said that the best PPE is PPE that people wear, and PPE worn repeatedly over a long time is going to be PPE that allows the person to feel as if they are not wearing it. As an example of one approach to designing PPE, she cited Flo Masks, which won the Biomedical Advanced Research and Development Authority (BARDA) Mask Challenge. The designers did anthropometric scanning of children’s faces, and those data enabled the company to design two mask sizes across adults and children that better fit people with shallower nose bridges.

Worple said that global harmonization of standards can help with design strategies to decrease confusion about what PPE to use in which settings. “I think the education piece, as well as a consistent message and a consistent set of performance requirements, would go a long way,” he said. Smit added that the standards for a pandemic might differ from those for regular occupational settings and dangers. At the same time, he said, it is important to include in standards guidance things such as using disposable PPE more than once and how to disinfect an N95 respirator without damaging the material. “If people are looking for extended use of PPE, they should be directed toward PPE made for extended use, such as elastomeric respirators, but if people are looking for PPE that they will wear for an hour and then dispose, then disposable PPE such as an N95 respirator or surgical mask might be more effective,” said Smit.

Sokolowski, who works mostly in the sports industry, said in one tool she uses, called wear-testing, users provide continuous feedback on how a product is performing and fitting (NC State, n.d.; Sokolowski et al., 2022). She noted that there is often a gap in communication between the user and manufacturer and raised the possibility that standards organizations could better document such challenges and create a database of knowledge so designers are not repeating the same mistakes.

Jaqua commented that having performance standards across a wide variety of commercially accessible PPE, as well as performance standards that a small manufacturer could use to produce a design for an individual,

would benefit individuals in the disabled community. Schneider agreed with this idea and pointed out that lessons learned from such a niche application could benefit PPE design more broadly.

A few members of the public attending the workshop commented on developing PPE for different workers and users based on input from those stakeholders. One individual, for example, wanted to know why NIOSH does not mandate that manufacturers produce a respirator suitable for a woman’s facial structure given that more women than men work in health care. Another participant noted that partners left out of standards development include those with facial hair, especially when shaving is not an option, such as on occupational (e.g., wildland firefighting) or religious grounds. One participant pointed out that since fit testing is not mandated for the public, it would be a good idea to have a take-home guides available to promote proper mask and respirator use.

Tredinnick said that in addition to performance standards as an important aspect of helping everybody understand which PPE to use in which applications, it is also important, as seen in the case of respiratory protection, to have a broader approval program in place. A more comprehensive approval program, such as NIOSH’s approval program for respirators, would include requiring a quality control program to ensure that manufacturers continue to have the same level of high-quality performance throughout the lifetime of a product in the market, as well as post-market product testing to ensure they continue to meet the standards. “That has been a really important differentiator between the N95 respirator and some of the other filtering facepiece respirator standards that are out there,” she said. A workshop participant noted that respirator test standards require methods that assume a particular product shape or composition, but it would be helpful if this effort reviewed standards for instances of technical bias.

Holm asked the panelists for their ideas on what other perspectives could be involved in the design of standards related to PPE design. Schneider replied that it is important to look at users of all types and test PPE in the field. “I think that is just as important as making sure we have the right people at the table,” she said. “Giving people at the table and others a chance to test drive is clearly a need.”

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