Comparison of three different real time particle measuring instruments

The Hunter Valley in New South Wales contains many open-cut coal mines and there is widespread interest in quantifying the contribution which mining and associated activities makes to particle concentrations in the local airshed. A study in the Hunter Valley to examine possible sources for measured particulate emissions has deployed three different instruments (TEOM, OSIRIS and GRIMM spectrometer) capable of determining fine particle concentrations. Of these instruments the TEOM is the only instrument that provides a direct mass measurement. The other two instruments use optical methods to infer particle mass and concentration. The current paper compares the response of all three different types of instruments when exposed to the same air mass. The paper also discusses, briefly, the issue of harmonisation of TEOM data, and by association, OSIRIS and GRIMM data, with reference methods.