Particulate matter indoors: a strategy to sample and monitor size-selective fractions

Particulate matter (PM) is an important player in indoor air quality.Even though PM limit values are in force for more than a decade inEurope and reference methods are well in place for ambient air,measuring indoor PM concentration still remains a challenge andstandardizing a measurement protocol is complex. As people staymost of their time indoors, indoor PM is of great interest in terms ofpublic health, as concentration can be drastically different to theone outdoors. This review aims to provide key information to theindoor air monitoring communities, to better understand principalmethods suitable for the analysis of indoor PM with their respectivemain influencing parameters. Advantages and drawbacks of eachmethod are discussed and specific awareness is raised to avoidwrong data interpretation in specific situations. The inter-instrumentdeviation is also explained and, when possible, methods to correctare proposed.