Sample ISO 9001 Quality Manual - ASQ

The outer fabric has a mesh warp-knit structure that provides a strong scaffolding for the inner particle filter layer, without obstructing the passage of air. The particle filter layer is made of strong yet lightweight 50 gsm non-woven polypropylene that offers very little resistance to air flow and yet still blocks the passage of even small fluid particles. Ethical Clothing Australia ... ................
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