The main objective of the article is to assess the changes in carbon dioxide emissions in residential sector caused by the implementation of the plans contained in the Air Protection Programs, anti-smog resolutions adopted in 9 voivodeships and the nationwide “Clean Air” program. The reduction of emissions of pollutants which directly affecting air quality and human health, i.e. particulate matter and benz(a)pyrene, which residential sector is the main source, can also affect the amount of emitted of carbon dioxide. To determine the changes in carbon dioxide emissions in the residential sector, emissions of CO2 in base year of 2017 from various energy carriers were determined, plans for reducing of low-stack emission were reviewed and the future structure of energy carriers used in households was estimated. The processes of increasing the efficiency of energy use through both the replacement of boilers and thermomodernization were also taken into account. The obtained results show that the highest CO2 emission reduction of 6% is achieved in case of “Clean Air” program. In frame of this program in 3.5 million of single-family houses a heating system replacement and thermomodernization is planned. Implementation of plans included on Air Protection Programs and anti-smog resolutions can lead to a relatively small (approx. 1%) reduction of CO2 compared to base year 2017. The detailed results of future fuel consumption and CO2 emission for individual voivodeships and for the whole of Poland was presented.

Structural safety is a concept defined in various ways, usually in an imprecise and qualitative manner. The article refers to the more important concepts and methods of structural safety assessment and presents an original proposal for a multi-faced assessment of this feature. Suggested procedure allows to take into account most of the key properties determining the safety of structures, including reliability, risk, resistance and robustness, random and non-random uncertainty of state variables and assessment criteria, potential consequences of failure, and makes possible the visualization of the results. Using the concept of fuzzy numbers, fuzzy statistics and the approximate reasoning scheme it enable to take into account subjective and qualitative information about the state variables, safety criteria, computational method, the professional knowledge and intuition of the designer. The application of the proposed procedure is illustrated on the example of the safety assessment of a reinforced concrete beam designed for flexure. The proposed procedure may be useful at the stage of conceptual design of building structures, as well as for assessing the safety of existing structures.