ASTM published a new standard called “Standard Specification for Barrier Face Coverings” (ASTM F3502) this week. This standard specification for face coverings gives suggested design, performance testing, and labelling instructions for general public face coverings. In general, face coverings should be designed to fit to the face snugly, are tested for filtration efficiency and inhalation resistance, should have labelling which helps the end user determine the appropriate fit of the product, and instructions for laundering re-usable products. This specification is an important step forward as it will give a framework for general use face coverings to follow, and help the public make a better educated decision about what they are using when they go out.
The testing includes an evaluation of filtration efficiency and breathability, which are important performance characteristics of a barrier face covering. Filtration efficiency is determined using a 4-15 second filtration test and an aerosol of sodium chloride with a count median diameter of 75 ± 20 nm. Airflow resistance for inhalation is measured using the automated airflow resistance measurement taken by the instrument which measures filtration efficiency and should be measured at the same face velocity as the filtration efficiency testing. Fit is assessed using design properties and appropriate sizing and may optionally be measured according to ASTM F3407, and labelling requirements include appropriate sizing, care instructions for the user, and a compliance statement indicating which level the performance testing achieved.
For the duration of the pandemic, ASTM is offering their relevant standards to the general public free of charge. By creating a free account on their website you can enter their reading room to read, download, or print these standards. Nelson Laboratories offers testing for inhalation resistance and filtration efficiency according to ASTM F3502. If you are interested in a quote for the filtration efficiency and airflow resistance testing, please contact our sales team.