KS B ISO 13347-3:2020 Industrial fans — Determination of fan sound power levels under standardized laboratory conditions —Part 3: Enveloping surface methods
2020KS B ISO 13347-3:2020 Industrial fans — Determination of fan sound power levels under standardized laboratory conditions —Part 3: Enveloping surface methods
2005KS B ISO 13347-3:2005 Industrial fans-Determination of fan sound power levels under standardized laboratory conditions-Part 3:Enveloping surface methods