ASTM level is at least level one, Level 2 is mprotection and level 3 is highest level. Level 2 and 3 is . VFE and PFE is most important 3 layers Earloop surgical mask Europe America standard ASTM AT LEAST level 1 or EN14683 Asia Pacific standard PFE level > 99% ( most important) VFE level > 99% ( most important) BFE level > 99%