This International Standard specifies methods for determining<\/p>\n
the insertion loss, in frequency bands, of ducted silencers with and without airflow,<\/p>\n<\/li>\n
the sound power level, in frequency bands, of the flow noise (or regenerated sound) generated by ducted silencers,<\/p>\n<\/li>\n
the total pressure loss of silencers with airflow, and<\/p>\n<\/li>\n
the transmission loss, in frequency bands, of air-terminal units.<\/p>\n<\/li>\n<\/ul>\n
The measurement procedures are intended for laboratory measurements at ambient temperature. Measurements on silencers in situ<\/i> are specified in ISO 11820.<\/p>\n
It is to be noted that the results determined in a laboratory according to this International Standard will not necessarily be the same as those obtained in situ<\/i> (installation), as different sound and flow fields will yield different results. For example, the pressure loss will be lower under laboratory conditions than in situ, but will be comparable between different laboratories.<\/p>\n
This International Standard is applicable to all types of silencer including silencers for ventilating and airconditioning systems, air intake and exhaust of flue gases, and similar applications. Other passive air-handling devices, such as bends, air-terminal units or T-connectors, can also be tested using this International Standard.<\/p>\n
This International Standard is not applicable to reactive silencers used for motor vehicles.<\/p>\n
\nNOTE 1 Annex A specifies the sound field excitation equipment. Annex B gives requirements for the transition element. Annex C gives details of duct walls and limiting insertion loss. Annex D specifies how to convert one-third-octave band attentuation values to octave band values. Annex E gives requirements for measurements on large parallel-baffle silencers. Annex F specifies a test of longitudinal attenuation. Annex G gives guidelines on anechoic terminations and Annex H shows examples of measurement arrangements.<\/p>\n<\/blockquote>\n
\nNOTE 2 Acoustic testing of air-terminal devices and fan-coil units is to be carried out as described for air-terminal units.<\/p>\n<\/blockquote>\n
\nNOTE 3 Sound power measurements on air-terminal units are specified in ISO 5135. Measurements of the pressure loss of air-terminal units are described in EN 12238, EN 12239 and EN 12589.<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"
Acoustics. Laboratory measurement procedures for ducted silencers and air-terminal units. Insertion loss, flow noise and total pressure loss<\/b><\/p>\n
\n\n
\n Published By<\/td>\n Publication Date<\/td>\n Number of Pages<\/td>\n<\/tr>\n \n BSI<\/b><\/a><\/td>\n 2010<\/td>\n 60<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":281588,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[1266,2641],"product_tag":[],"class_list":{"0":"post-281582","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-91-120-20","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/281582","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/281588"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=281582"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=281582"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=281582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}