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Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	As with the IEST standard for filters, the EN 18221 also includes classifications of other types of HEPA and ULPA filters, however, none is required for use in biological safety cabinets.
http://www.w3.org/ns/prov#wasQuotedFrom	pharmaguideline.com