The regulations require that you calibrate your sound level meter both before and after taking measurements. Therefore it’s important that you also select a suitable acoustic calibrator to go with your noise meter or analyser. If you’re renting a class 2 instrument or dosimeter then you can use a class 1 or class 2 calibrator but if its a class 1 instrument then it has to be a class 1 calibrator. We also carry a range of vibration calibrators for field or lab work.