ISO 6926:2016 声学 噪声源的声功率级的测定 基准声源的性能和校正要求

标准编号：ISO 6926:2016

中文名称：声学 噪声源的声功率级的测定 基准声源的性能和校正要求

英文名称：Acoustics — Requirements for the performance and calibration of reference sound sources used for the determination of sound power levels

发布日期：2016-01

标准范围

This International Standard specifies the acoustical performance requirements for reference soundsources:— temporal steadiness (stability) of the sound power output;— spectral characteristics;— directivity.Temporal steadiness is defined in terms of the standard deviation of repeatability (see 5.2). Thespectral characteristics can be verified in either a hemi-anechoic room or a reverberation test roomfrom measurements of the frequency band sound power levels in accordance with this InternationalStandard (see 5.4). The performance requirements on directivity index can only be verified in a hemianechoicroom (see 5.5.)This International Standard also specifies procedures for providing level calibration data anduncertainty on a sound source intended for use as a reference sound source in terms of its sound powerlevel under reference meteorological conditions as defined in Clause 4 in octave and in one-third-octavebands, and with frequency weighting A.This International Standard is titled as a calibration standard even though the method is conducted ina testing laboratory and the level calibration results are not directly traceable to national standards ofmeasure in a strict metrological sense. Testing laboratories performing this method are not expectedto meet all requirements normally associated with a calibration laboratory.NOTE ISO/IEC 17025[15] specifies different requirements for the competence of testing laboratories andcalibration laboratories respectively. Laboratories testing reference sound sources in accordance with thisInternational Standard would typically comply with the requirements for testing laboratories but not necessarilywith those for calibration laboratories.This International Standard specifies methods to calibrate reference sound sources not only in afree field over a reflecting plane but also in reverberation test rooms at different distances from theboundary surfaces. For the position of the reference sound source on one reflecting plane, the twodifferent test environments mentioned above are considered equivalent for frequency bands above orequal to 200 Hz. At 160 Hz and below, some systematic differences can occur (see 11.2). For frequenciesbelow 100 Hz, an alternative calibration method using sound intensity is given.The sound source can either be placed directly on the floor or mounted on a stand to be used at acertain elevation above the floor. According to this International Standard, stand-mounted sources arecalibrated in reverberation test rooms. Floor-mounted sources are either calibrated in hemi-anechoicor in reverberation test rooms. For floor-mounted sources in hemi-anechoic rooms, this InternationalStandard is valid only for sources whose maximum vertical dimension is less than 0,5 m and whosemaximum horizontal dimension is less than 0,8 m. According to this International Standard, only floormountedreference sound sources can be used when carrying out measurements on a measurementsurface. For reference sound sources to be used or calibrated under reverberant conditions, no suchrestrictions on maximum dimensions apply.

标准预览图