ASC Whetlerite charcoal

The effectiveness of modern masks depends on both physical adsorption and chemical inactivation of the threat agent. For example, in the M17 protective mask the adsorbent, known as ASC Whetlerite charcoal, is charcoal impregnated with copper oxide and salts of silver and chromium.6 The M40 protective mask uses an ASZ impregnated charcoal, which substitutes zinc for the hexavalent chromium (CrVI). The Centers for Disease Control and Prevention and the National Institute for Occupation... 

Liang, S. H. Harrison, B. H. Pagotto, J. G. Analysis ofTEDA on ASC-Whetlerite Charcoal Defense Research Establishment, Ottawa. Available at httD //handle.dtic.mil/100.2/ADA192035. 

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