Relationship between indoor ambient dose equivalent rates and the architectural style of standalone houses in locations with high naturally occurring radionuclide soil concentrations.

There have been numerous studies relating house construction materials with the indoor gamma dose rate mainly coming from natural radionuclide activities. The relationship between the outdoor gamma dose rate and the soil's naturally occurring radionuclide content is well documented. Few studies, however, have investigated the historical evolution of indoor gamma dose levels due to the principal materials used in house construction in geographical areas where outdoor natural radiation levels are significant. The present work was carried out in an area of Spain with high outdoor gamma dose levels (on average, 0.267 µSv h-1) due to the natural radioactive characteristics of its soils, considering a great variety of standalone houses built from the beginning of the 18th century until today with different styles, architectural techniques, and materials in their construction. The measured ambient dose equivalent rates in thgese houses decreased the more recent the date of their construction was. In conclusion, today's architectural style for housing, which uses materials of practically universal origin, not only attenuates part of the irradiation due to the composition of a location's soils but also contributes less to the indoor gamma dose rate due to the relatively low naturally occurring radionuclide concentration of modern building materials.

Influence of architectural style on indoor radon concentration in a radon prone area: A case study.

Indoor radon is a major health concern as it is a known carcinogenic. Nowadays there is a trend towards a greater energy conservation in buildings, which is reflected in an increasing number of regulations. But, can this trend increase the indoor radon concentration? In this paper, we selected a radon prone area in Spain and focused on single-family dwellings constructed in a variety of architectural styles. These styles ranged from 1729 up to 2014, with varying construction techniques (from local resources to almost universally standard building materials) and regulations in force (from none to the Spanish regulation in force). The 226Ra concentrations in soil and surface radon exhalation rates were rather similar in this area, mean values ranging 70-126Bq/kg and 49-100mBq/m2·s, respectively. Indoor radon concentration was generally greater than the contribution from soil exhalation (surface exhalation rates), especially in New dwellings (1980-2014). Its concentration in dwellings built in the Traditional style (1729-1940) was significantly lower than in the new houses. This can be consequence of the air tightness of the dwellings as a consequence of the different regulations in force. In the period covered by the Traditional style, there was no regulation in force, and dwelling had loose air tight. Whereas in recent times, there are mandatory regulations assuring a better air tightness of the buildings. Refurbishment of Traditional dwellings also seems to increase the indoor radon concentration, as they must also comply with the regulations in force.