DIN EN ISO 17201-3:2010-06

This part of ISO the ISO 17201 and EN ISO 17201 standard series, respectively, has been prepared by ISO/TC 43/SC 1 "Noise", in collaboration with CEN/TC 211 of the same name, the secretariats of which are held by DS (Denmark). On the national level, the Committee responsible for this part 3 is Mirror Committee NA 001-01-02-07 AA "Akustik - Geräusche von Schießplätzen" ("Acoustics - Noise from shooting ranges"). This part 3 of the ISO 17201 standard series provides guidance for the user on calculating sound propagation of shooting sounds. If no corresponding calculation procedures in the form of rules or regulations have been specified by local or national authorities and no additional calculation procedures to those given in ISO 9613-2 are available, then ISO 9613-2 may be applied, provided that the framework and recommendations specified in part 3 are taken into account. The prediction of the sound exposure level of the shooting sound at certain reception points is based on single shots. Thereby the prediction is based on the angular source energy distribution of the muzzle blast measured in accordance with ISO 17201-1 or calculated in accordance with ISO 17201-2. Part 3 of ISO 17201 applies to weapons with calibres of less than 20 mm, explosive charges of less than 50 g TNT equivalent, takes into account the projectile sound and is applicable at distances where the peak pressure and the peak pressure level are less than 1 kPa or 154 dB, respectively. Part 3 of the ISO 17201 standard series provides specific recommendations on how source data can be adapted for use with ISO 9613-2 to estimate the sound levels to be expected in the neighbourhood around shooting ranges. The source energy of the muzzle blast is typically measured or calculated for free field conditions and often exhibits strong directivity. However, in many cases weapons are fired within shooting ranges which have structures such as firing sheds, walls or safety barriers. Furthermore, it shall be taken into account, that particularly shot guns are fired in different directions. This is especially the case when doing trap and skeet shooting on clay targets. It is a general requirement that for shooting sounds in so-called non-open field situations more sophisticated calculation models - compared to ISO 9613-2 - shall be applied. This applies, amongst other things, to the boundary element method (BEM), ray tracing models, more sophisticated models or combinations thereof, in which reflection, diffraction and scattering and specific weather conditions are taken into account in more detail. On this basis in part 3 a so-called "benchmark case" has been established as a test module. Thereby it is regulated that, where sophisticated calculation models for shooting noises are used, which deviate from the boundary element method, it shall always be ensured that sound exposure levels calculated that way do not significantly deviate from the boundary element method. The specification and adaptation of corresponding calculation procedures are completed by a large number of calculation examples and the determination of the uncertainty budget. This standard promotes innovation and takes into account new research results with regard to sound propagation of shooting sounds and addresses, amongst other things, acoustic consultants and authorities who deal with the determination or specification of sound exposure of shooting ranges.