The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value) of white/yellow phosphorus of 0.1 mg/m3 and evaluated the MAK value of red phosphorus, considering all toxicity endpoints. Available unpublished study reports and publications are described in detail. Data is limited and no repeated dose studies are available for red phosphorus and it is assigned to Section II b of the List of MAK and BAT values. Inhalation studies in animals or humans are not available for white/yellow phosphorus. The systemic NOAEL in rats is 0.015 mg/kg body weight and day in a one‐generation study. Therefore, the MAK value is reduced to 0.05 mg/m3. Using a read‐across to the oxidation product phosphorus pentoxide or to phosphoric acid, one of the acids formed during oxidation in humid air, both with MAK values of 2 mg/m3, no irritant effects are expected for white/yellow phosphorus at 0.05 mg/m3. As the MAK value is based on a systemic effect, white/yellow phosphorus is reclassified in Peak Limitation Category II. No data are available from which a substance‐specific excursion factor could be derived, therefore the default excursion factor of 2 is assigned. No risk to the foetus is expected if the MAK value is observed. No data on sensitizing effects of white phosphorus are available. The only available genotoxicity data are negative mutagenicity tests in Salmonella typhimurium. Valid carcinogenicity studies are not available. No prolonged skin contact to white/yellow phosphorus is possible due to its burning and corrosive effects and owing to the poor water solubility of phosphorus, the calculated quantities penetrating through skin are not expected to contribute significantly to systemic toxicity.