Occupational exposure to anaesthetic gases (halothane, forane and nitrous oxide) was assessed in hospitals located in Lódź and its satellite towns. Individual dosimetry and stationary sampling methods were employed. The samples of air from workplaces were analysed by gas chromatography with mass detection or flow ionisation (halothane, forane) and by infra-red spectroscopy method (nitrous oxide). The concentrations of halothane and accompanying substances (ethanol, isopropanol and diethyl ether) indicate that Polish OELs were met in the majority of the hospitals. As Polish hygiene standards for forane and nitrous oxide are no available, the concentration values were compared with Swedish and German OELs. The comparison revealed that forane concentrations did not exceed Swedish OEL but nitrous oxide did exceed German maximum allowable levels.