Solar radiation can not only help but it can be harmful as well. It is necessary to pay increased attention especially in the case of classical solariums with regard to the radiation spectrum. Nevertheless, this does not apply to our 12m2 large sunsky because its characteristics of the radiated spectrum approaches composition of natural solar radiation – it features the same spectral range as natural solar radiation to which human organism is used. The radiators contain not only a share of medium-wave and short-wave infrared rays but also coloured light and long-wave UV-A and UV-B radiation. Besides this, the necessity of being closed in narrow cells of classical solariums is eliminated.