ISO 11904-1-2002 pdf download.Acoustics – Determination of sound immission from sound sources placed close to the ear- Part 1: Technique using a microphone in a real ear (MIRE technique). This part of ISO 11904 specifies basic framework measurement methods for sound immission from sound sources placed close to the ear. These measurements are carried out with miniature or probe microphones inserted in the ear canals of human subjects. The measured values are subsequently converted into corresponding free-field or diffuse-field levels. The results are given as free-field related or diffuse-field related equivalent continuous A-weighted sound pressure levels. The technique is denoted the microphone-in-real-ear technique (MIRE technique). This part of ISO 11904 is applicable to exposure from sources close to the ear, for example during equipment tests or at the workplace by earphones or hearing protectors with audio communication facilities. This part of ISO 11904 is applicable in the frequency range from 20 Hz to 16 000 Hz. 2 Normative references The following normative documents contain provisions wt,ich, through reference in this text, constitute provisions of this part of ISO 11904. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based…

BS EN ISO 3744-2010 pdf download.Acoustics – Determination of sound power levels and sound energy levels of noise sources using sound pressure – Engineering methods for an essentially free field over a reflecting plane (ISO 3744:2010). BS EN ISO 3744 specifies methods for determining the sound power level or sound energy level of a noise source from sound pressure levels measured on a surface enveloping the noise source (machinery or equipment) in an environment that approximates to an acoustic free field near one or more reflecting planes. The sound power level (or, in the case of noise bursts or transient noise emission, the sound energy level) produced by the noise source, in frequency bands or with A-weighting applied, is calculated using those measurements. NOTE Differently shaped measurement surfaces can yield differing estimates of the sound power level of a given noise source and an appropriately drafted noise test code (see ISO 12001) gives detailed information on the selection of the surface. 1.2 Types of noise and noise sources The methods specified in this International Standard are suitable for all types of noise (steady, non-steady, fluctuating, isolated bursts of sound energy, etc.) defined in ISO 12001. This International Standard is applicable…

ISO 3745-2012 pdf free.Acoustics – Determination of sound power levels and sound energy levels of noise sources using sound pressure – Precision methods for anechoic rooms and hemi-anechoic rooms. ISO 3745 specifies methods for measuring the sound pressure levels on a measurement surface enveloping a noise source (machinery or equipment) in an anechoic room or a hemi-anechoic room. The sound power level (or, in the case of impulsive or transient noise emission, the sound energy level) produced by the noise source, in frequency bands of width one-third octave or with frequency weighting A applied, is calculated using those measurements, including corrections to allow for any differences between the meteorological conditions at the time and place of the test and those corresponding to a reference characteristic acoustic impedance. In general, the frequency range of interest includes the one-third-octave bands with mid-band frequencies from 100 Hz to 10 000 Hz. In practice, the range is extended or restricted to frequencies beyond or within these limits, to those between which the test room is qualified for the purposes of the measurements. 1.2 Types of noise and noise sources The methods specified in this International Standard are suitable for all types of noise (steady,…

ISO 3382-3-2012 pdf free download.Acoustics – Measurement of room acoustic parameters – Part 3: Open plan offices. This part of ISO 3382 specifies methods for the measurement of room acoustic properties in open plan offices with furnishing. It specifies measurement procedures, the apparatus needed, the coverage required, the method for evaluating the data, and the presentation of the test report. The measurement results can be used to evaluate room acoustic properties in open plan offices. This part of ISO 3382 is intended for medium and large size open plan offices. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3382-1. Acoustics — Measurement of room acoustic parameters — Part 1: Performance spaces ISO 3740, Acoustics — Determination of sound power levels of noise sources — Guidelines for the use of basic standards ISO 3744, Acoustics — Determination of sound power levels and sound energy levels of noise sources using sound pressure — Engineering methods for an essentially free field over a reflecting plane ISO 14257, Acoustics — Measurement and parametric description…

ISO 532-1-2017 pdf free.Acoustics一Methods for calculating loudness一Part 1:Zwicker method. Then, for each band a slope towards the higher critical band is added, and the area below the distribution of specific loudness is summed. The specific value of the slope to be added depends on the respective one-third-octave-band levels and centre frequencies. Again, detailed information can be found in the above mentioned graphical representations or in the tables of j respectively. Having entered the corrected one-third-octave-band levels into the diagram, the shape of the specific loudness pattern starts with a vertical rise to the one-third-octave-band level measured, stays at the main value corresponding to the one-third-octave-band level in question and then falls with a slope unless the level is higher in the next one-third-octave band, in which case the pattern rises vertically to the level appropriate for the next one-third-octave band. Both the one-third-octave-band spectrum and the loudness pattern are highlighted by solid curves in the diagram of Figure 2. If the next one-third-octave-band level is lower, the decrease of the specific loudness towards higher centre frequencies follows the broken lines, corresponding to the upper slope. In this way, the final specific loudness versus critical band rate pattern, shortened to “loudness…