Air sampling is used to measure an individual’s exposure to a chemical (e.g. dust or gas) when compared to an exposure limit. Personal air sampling pumps are used with sampling accessories and media (filters and tubes) to collect the substance, which can then be sent to a laboratory for analysis. This will then give an 8 hour exposure value. Real time dust monitors are also available to give instantaneous dust levels, which will give an idea of when exposure occurred and an indicative level in real time.