1.1 This specification is primarily intended to help ensure barrier face coverings meeting the stated requirements provide (1) a means of source control for individual wearers by reducing the number of expelled droplets and aerosols from the wearer’s nose and mouth into the air; and (2) to potentially offer a degree of particulate filtration to reduce the amount of inhaled particulate matter by the wearer.
Note 1: The source control/protection provided by barrier face coverings depends on several factors not considered in this specification, such as material degradation from wearer challenges including perspiration, talking, sneezing, and the length of time the barrier face covering is worn. Further research is needed to expand the evidence base for the protective effect of face coverings and, in particular, to identify the combinations of materials that maximize both their blocking and filtering effectiveness, as well as fit, comfort, durability, and consumer appeal. (https://www.cdc.gov/coronavirus/2019-ncov/more/masking-science-sars-cov2.html.)
Note 2: There are currently no established methods for measuring outward leakage from a barrier face covering, medical mask, or respirator. Nothing in this standard addresses or implies a quantitative assessment of outward leakage and no claims can be made about the degree to which a barrier face covering reduces emission of human-generated particles.
1.2 This specification establishes minimum design, performance (testing), labeling, user instruction, reporting and classification, and conformity assessment requirements for barrier face coverings.
1.2.1 Design criteria include setting minimum areas of face coverage over the wearer’s nose and mouth, prohibiting open vents or valves, requiring a means for retaining the barrier face covering on the wearer’s head, and providing a representation of product sizing. Manufacturers are further required to perform a design analysis for assessing leakage of exhaled air from the barrier face covering. Manufacturers are permitted to conduct quantitative testing as specified in this standard to supplement the design analysis.
1.2.2 Performance and testing criteria define minimum barrier face covering filtration efficiency and airflow resistance performance properties. Sub-micron particulate filtration efficiency represents the ability to capture and reduce respirable droplets and aerosols that potentially contain viruses and bacteria. Airflow resistance represents the wearer’s ease of breathing or breathability while wearing the barrier face covering. The impact of repeated cleaning or laundering on continued performance is applied for measuring performance properties for those barrier face coverings that are intended to be reusable. Manufacturers are permitted to also provide test results for bacterial filtration efficiency (BFE) as supplemental information to the mandatory performance measurement of sub-micron particulate filtration efficiency.
Note 3: The principal performance criteria for barrier face covering determined by testing are sub-micron particle filtration efficiency and airflow resistance. Quantitative leakage assessment testing is optional for information purposes and is not required. This testing is not likely to be representative of outward leakage from the barrier face covering and should not be claimed to represent the amount of source control offered by the face covering. Bacterial filtration efficiency testing is also optional and not required. It is significantly different than sub-micron filtration efficiency, and the results of BFE testing cannot be interchanged or directly compared. The scope of this standard does not include accessories to barrier face coverings.
1.2.3 Labelling requirements specify the minimum content for labels that appear on the barrier face covering, its immediate packaging, and if different, point-of-sale packaging.
1.2.4 User instructions are required to guide selection and sizing, proper use (positioning and adjustment), and care including cleaning or laundering if product reuse is intended; inform on product cautions and limitations; and describe product replacement and disposal procedures.
1.2.5 Conformity assessment is demonstrated following Guide , Annex A3, Model A to issue a declaration of conformity indicating that each barrier face covering labelled as compliant has met all of the requirements of this standard specification including design criteria, performance criteria, test methods, labelling, and user information. Additionally, conformance to this standard requires that sub-micron particulate filtration efficiency and airflow resistance tests have been performed by a laboratory accredited for conducting these tests.
1.3 This specification addresses all barrier face coverings and only barrier face coverings that are intended for either a single use (disposable) or multiple uses (reusable).
1.4 This specification does not address the unique additional performance attributes of barrier face coverings that exist for certain applications, such as flame-resistant apparel used in environments where there are flame, high heat, electrical arc, or related hazards, but does recommend that barrier face coverings also conform to other standards as applicable.
1.5 This specification does not address the use of antimicrobial or antiviral materials, finishes, or mechanisms.
Note 4: The use of antimicrobial materials, finishes, or mechanisms is generally subject to regulatory oversight by government agencies, including the U.S. Environmental Protection Agency and U.S. Food and Drug Administration in the United States, which applies additional safety and efficacy requirements to these products. See for the requirement of nontoxic and non-irritating materials used in the construction of barrier face coverings.
1.6 This specification does not address requirements for medical face masks, which are covered in Specification .
1.7 Nothing in this specification is intended to contradict or replace criteria that are established in 42 CFR Part 84 for air-purifying respirators or requirements for use of respirators in accordance with 29 CFR 1910.134.
1.8 Nothing in this specification is intended to imply that barrier face coverings qualify as approved respiratory protection devices or have FDA clearance for use in a healthcare setting.
1.9 Nothing in this specification is intended to imply that barrier face coverings should be placed on very young children (<2 years), anyone who has trouble breathing, or anyone who is unconscious, incapacitated, or otherwise unable to remove barrier face coverings without assistance.
1.10 The values stated in SI units or in other units shall be regarded separately as standard. The values stated in each system must be used independently of the other, without combining values in any way.
1.11 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.12 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.