Due to high humidity, high air temperature and hazardous compounds including chlorine indoor swimming pools are called as ‎unhealthy environment. Therefore, the pollutants’ concentration, relative humidity and thermal comfort conditions must be ‎simultaneously considered in designing the air conditioning systems of indoor swimming pools. In this study, a new approach has been ‎presented for concurrent modeling of water evaporation mechanism, chlorine concentration level, occupants’ thermal sensation and ‎temperature and velocity fields in a championship-size indoor swimming pool. In this regard, a new algorithm has been developed in ‎order to apply adaptive boundary conditions at water-air interface in the pool. In the mentioned pool, the air enters the environment ‎through a linear ceiling diffuser at temperature of 35°C, relative humidity of 30% and air exchange rate of 4 times per hour. The results ‎show that the distribution of temperature, relative humidity and concentration of chlorine contaminant are significantly depending on the ‎height from the water surface. So, the volumetric average of relative humidity from the floor to 0.5m height is about 62%; while the ‎volumetric average of relative humidity in the occupied zone is about 50%. Moreover, results indicate that in the distance of floor to 0.5m ‎height, the mean value of chlorine’s concentration is about 60% larger than its mean value in the occupied zone. Also, the temperature ‎field and distribution of thermal comfort index are significantly dependent to the height.‎