When air sampling for hazardous substances we always follow validated methods such as those details in the HSE MDHS series. For example MDHS 14/4 For total inhalable and respirable dust. Or MDHS 96 for volatile organic compounds in air. Where there are no appropriate MDHS methods the NIOSH or OSHA methods can be adopted. It is important to realise the limitations of sampling methods in terms of the detection limit and efficiency of sampling.
In the case of LEV testing we follow the technical guidance for the performance of extraction systems and also the guidance in the HSE document HSG 258.
In the same way with noise we follow the guidance detailed in the HSE website and the methodologies for taking noise measurements and allowing for the calculations of occupational exposure from those measurements. In some instances we may use noise dosimeters to determine noise exposure.
The equipment for air sampling such as flow calibrators or in the case of LEV the flow measurement equipment and for noise the noise analyser are externally calibrated on an annual basis.
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