Chloroforme is formed during disinfection of swimming pool water in certain amounts depending on several cofactors. Because of its carcinogenic properties this compound has been frequently a subject of public discussion over the last couple of years. Little is known about chloroforme concentrations in spas. Spas are operated at significantly higher temperatures as compared to other pools, and the organic contamination may be higher. Therefore, chloroforme is possibly produced in higher amounts than in regular swimming pools. On the other hand the air that is blown through the bassin may reduce the concentration of this low volatile substance. In order to investigate the average concentration, 21 water samples from spas in public indoor pools were analyzed as to their chloroforme contend. The median of concentration was 3.8 micrograms/l. The maximum measured chloroforme concentration was 6.4 micrograms/l. The average chloroforme concentration in the filtered water was slightly higher than before filtration. The use of spas does not implicate an increase in chloroforme uptake by bathers.