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BS 4718:1971被替代

Methods of test for silencers for air distribution systems

出版:British Standards Institution

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基本信息
標(biāo)準(zhǔn)編號(hào): BS 4718:1971
發(fā)布時(shí)間:1971/4/22 0:00:00
標(biāo)準(zhǔn)類別:Standard
出版單位:British Standards Institution
標(biāo)準(zhǔn)頁(yè)數(shù):36
標(biāo)準(zhǔn)簡(jiǎn)介

Measurement of performance of unit silencers and silencing elements for ducted ventilating and air conditioning systems; aspects considered are attenuation of broad band airborne sound (insertion loss), generation of aerodynamic noise (generated noise level) by, and change in pressure in, air flowing through silencer. Methods measure insertion loss without airflow. Does not apply to silencers providing selective attenuation over narrow frequency bands, or to silencers designed for direct coupling to a fan or for sound insulation of partitions with ventilated openings.

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? British Standards Institution 2013

替代本標(biāo)準(zhǔn)的新標(biāo)準(zhǔn)

BS EN ISO 7235:2003