This document specifies a method for the determination of the time-weighted average mass concentration of hydrogen chloride (HCl) gas and hydrochloric acid mist, hydrogen bromide (HBr) vapour and hydrobromic acid mist and nitric acid (HNO3) vapour and mist in workplace air by collection on an alkali-impregnated quartz fibre filter and analysis by ion chromatography. For mist sampling, this method is applicable to the personal sampling of the inhalable fraction of airborne particles as defined in ISO 7708 and to static (area) sampling.