This document specifies methods for measuring the sound pressure level from service equipment in a building or from other sound sources inside or outside of the building. This document specifically covers measurements of sanitary installations, mechanical ventilation, heating and cooling service equipment, lifts, rubbish chutes, boilers, blowers, pumps and other auxiliary service equipment, and motor driven car park doors; however, it can also be applied to measurements of equipment or activities in in or nearby a building. To include noise from sport facilities, pubs etcetera inside or outside the building. The measurement of noise from external sound sources generating ground-borne noise are not included in this standard. The methods are suitable for rooms with volumes of approximately 300 m3 or less e.g. in dwellings, hotels, schools, offices and hospitals. The standard is generally not intended for measurements in large auditoriums and concert halls, nor where the source is located at a distance from the building where sound propagation may change with weather conditions. However, the operating conditions and operating cycles in Annex B can be used in such cases. The service equipment sound pressure level is determined as the maximum A-weighted and optionally C-weighted sound pressure level occurring during a specified operation cycle of the service equipment under test, or as the equivalent continuous sound pressure level in one third octave bands determined with a specified integration time. A-weighted and C-weighted values are calculated from one third octave band measurements or optionally from octave band measurements.