Also known as peroxyacetic acid (PAA). The colourless organic acid with a characteristic acrid odour belongs to the group of peroxy acids and arises upon treatment of acetic acid with hydrogen peroxide. The organic compound dissolves in water and is characterised by a strong oxidising effect. Due to the latter, it is used as bleaching agent, but also as disinfectant, e.g. for surface and instrument disinfection. Its spectrum of activity comprises Gram-negative bacteria, fungi and viruses. PAA's fixating properties in case of organic soils can have drawbacks when used as disinfectant.