Places that contain historical objects can suffer from a polluted interior atmosphere when they are not properly aired. These pollutants come in many forms, acids (such as methanoic and ethanoic acid) being one of them. The concentration of these acid atmospheric pollutants can be determined with passive samplers. According to their shape, these samplers can be divided into tube and badge samplers, while both of these types also come in diffusive and semi-permeable variants. Samples from these devices are analysed using instrumental techniques. To that end, separation techniques like gas, liquid, and ion chromatography are used most often.