With the beginning of cold weather in Moscow, as well as in the whole country, the heating period comes, which results in increased capacity of the fuel and energy complex to maintain normal temperatures in houses, which leads to increased emissions and impacts on the body of people living nearby. The most common are small gas-fired boilers. As an example, we used a gas boiler-house in one of Moscow city districts with the total capacity not exceeding 15 Gcal/hour. The calculation of non-carcinogenic and carcinogenic risks showed that people living in the exposure area are at risk of noncarcinogenic effects of acute exposure. Exposure is manifested in the form of worsening of general well-being, cough, headaches, however, there are no chronic and carcinogenic risks to the population.