Sound Level Meters

Sound Level Meters are calibrated in accordance with BS 7580 Part 1: 1997 unless otherwise requested. An optional UKAS-accredited service is available for most instrument types, and it is intended to offer calibrations in accordance with BS EN 61672 Part 3: 2006 as the demand becomes significant (please enquire). BS 7580 is designed for the verification of instruments constructed in accordance with BS EN 60651: 1994 and BS EN 60804: 1994, the standards to which the majority of the sound level meters in use today are designed, and which are not yet superseded in the measurement codes of practice.

In due course, it is to be expected that these instruments will gradually be replaced with the new generation conforming to BS EN 61672, but measurements with instruments satisfying either sound level meter standard are acceptable. Consequently, at least for the present, verification tests to BS 7580 Part 1: 1997 are acceptable for all sound level meters.

MTS Calibration achieved UKAS accreditation in 2007, and is unique amongst other calibration laboratories in including in its accredited sound level meter calibration a free-field microphone calibration across the full frequency range of the Type 1 sound level meter standard. This covers what in our experience is the most likely point of failure in the performance of a sound level meter – the normal requirement of BS 7580 Part 1: 1997 is for a check on the microphone at only three discrete frequencies (125Hz, 1000Hz, and 8000Hz); we believe that this is not sufficient to assure compliance with BS EN 60651: 1994.