{"id":281578,"date":"2024-10-19T19:01:36","date_gmt":"2024-10-19T19:01:36","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bs-en-iso-51362009\/"},"modified":"2024-10-25T15:40:51","modified_gmt":"2024-10-25T15:40:51","slug":"bs-en-iso-51362009","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bs-en-iso-51362009\/","title":{"rendered":"BS EN ISO 5136:2009"},"content":{"rendered":"

This International Standard specifies a method for testing ducted fans and other air-moving devices to determine the sound power radiated into an anechoically terminated duct on the inlet and\/or outlet side of the equipment.<\/p>\n

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NOTE 1 For the sake of brevity, wherever the term \u201cfan\u201d occurs in the text, it means \u201cfan or other air-moving device\u201d.<\/p>\n<\/blockquote>\n

The method is applicable to fans which emit steady, broad-band, narrow-band and discrete-frequency sound and to air temperatures between \u2212 50 \u00b0C and + 70 \u00b0C. The test duct diameter range is from 0,15 m to 2 m. Test methods for small (d < 0,15 m) and large (d<\/i> > 2 m) test ducts are described in the informative Annexes H and I, respectively.<\/p>\n

The maximum mean flow velocity at the microphone head for which the method is suitable depends on the type of microphone shield used, and is as follows:<\/p>\n