Analysis of the distribution of CO2 concentrations was performed for a water-and-steam boiler plant located in a detached building supplying thermal energy to a hospital. The boiler plant was equipped with two low-temperature boilers and one high-temperature steam boiler. The maximum thermal energy demand of the hospital was 4280, 3500 kW of which came from the hot-water boilers and the remaining 780 kW from the steam boiler. Due to the operating system there were no permanent job positions in the boiler plant. Servicing consisted only in the supervision, periodic adjustment and maintenance of the equipment. These kinds of working conditions release the employer from the necessity to perform tests and measurements of working conditions in such a building. On the other hand, continuous measurements are made because of the installation safety and emissions of pollutants into the environment. The article presents results of the measurements and analysis of the distribution of CO2 concentrations inside and outside a small boiler plant, due to which it was found that the level of carbon dioxide concentration did not depend on the ambient air temperature. The resulting values are similar regardless of whether the measurements were taken in December 2012 or April 2013. However, there is an evident impact of seasons on the concentrations in the indoor air associated primarily with the demand for heat during the given period, the stay of people in the workplace and the number of working devices.
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