41. Measurement of airborne noise emitted by machines ; enveloping surface method ; metal working machines , circular sawing machines 42. Industrial fans - determination of fan sound power levels under standardized laboratory conditions - enveloping surface method 43. Noise emitted by vessels on inland water - ways and harbours ; enveloping surface method for the determination of the sound power level 44. Measurement of airborne noise emitted by machines ; enveloping surface method ; turbogenerator sets for use in thermal power stations 45. Measurement of airborne noise emitted by machines ; enveloping surface method ; woodworking machines ; single blade circular saw benches 46. Measurement of noise emitted by machines ; airborne noise measurement , enveloping surface method ; electrical switchgear and control gear 47. Measurement of airborne noise emitted by maschines ; enveloping surface method ; woodworking machines ; multi - blade circular sawing machines 48. Measurement of airborne noise emitted by machines ; enveloping surface method ; shunting trolleys with friction - wheel and or gearwheel drive 49. Measurement of noise emitted by machines ; airborne noise emission ; enveloping surface method ; hydraulic assemblies test report specimen form 50. Measurement of airborne noise emitted by machines ; enveloping surface method ; metal processing machine , tools special , stipulations for lathes
