By-product gypsum, produced as a waste in the phosphate industry, could be used in bulk as a building material but it has a higher radium content than other building material. Reports an analysis of the dose rate that would result if gypsum were used for a two-storey, three-bedroom, centre terrace house. Discusses the dose from beta radiation, gamma radiation and radon gas,assuming one air change per hour.
Reports study of the emanating power of radon from building materials. Samples of material were placed in an air-tight glass container and the radon diffusing from the sample was measured in an electrostatically operated cylindrical steel chamber in which alpha particle scintillations were counted.< Gives main results for different building materials in the form of anemanation coefficient, defined as the ratio of migrating 222Rn to the 226Ra content in the sample. Materials tested were fly-ash, slag, by-product gypsum, red brick, silicon brick, portland cement, and soil.
Reports a nationwide investigation of gamma radiation in Swedish houses, made by the National Institute of Radiation Protection in Stockholm. The occupants of 2000 apartments and houses were picked at random and asked to participate in the investigation. The measurements were made with thermoluminescent dosimeters CaSO4 - Dy in teflon. Three detectors were sent to each of the selected dwellings by post. Finds that the accuracy of the detectors is about+ or - 25%.
The authors have developed a Fortran IV computer program for estimating whole body and lung dose equivalent rates due to naturally occurring radionuclides in building materials. Two of the inputs to this program are the effects of wall thickness and the effects of a surface sealant on the gamma exposure ratedue to the increased quantity of radon daughter nuclides trapped within a wall.
Reports study of the exhalation of radon from building materials by following the build-up of activity in closed vessels containing samples of the material. On the basis of a linear diffusion model, the porosity, diffusion length and radon production rate were found for a light-weight concrete by measuring theexhalation at various, constant pressures. The exhalation of radon from wallswas measured in a concrete-walled basement room by studying the growth of activity in exhalation cans sealed to various portions of the walls.
The daughter products of radon are chemically active materials which, when inhaled are very likely to deposit in the respiratory tract. Defines a special unit, the working level, to indicate the radiation burden from radon daughters. Reports study of exhalation rates from various building materials made by enclosing samples in containers and analysing air samples from the containers. Gives table of results. Discusses control of airborne radiation by increasing the ventilation rate, sealing room surfaces, mechanical circulation and filtration of the air.
This work deals with different aspects of air movements in building components. The investigation shows to what degree the concept of fluid mechanics can be applied to problems concerning air flows in building componenets. The applicable parts of fluid mechanics are presented as thoroughly as possible. Based on this concept, routines are outlined to make it possible to handle complex flow and pressure distribution problems. Both manual and computer calculation routines are described and the way they can be used is demonstrated in a number of examples.
Gives details of a method for determining the amount of radon emanating from a carbonate rock specimen. Analysis was first made with rock in solid form. An essay was then made with the material containing radium in a clear acid solution.< Discusses the need for the analysis of building material causing any type of abnormally high background variation. Outlines laws covering the buildup and decay of radon.
Reports measurements of concentrations of thorium, potassium, uranium radium, and relative radioactivity of building materials used in the United Kingdom. Gives table of results. Examines in particular calcined gypsum prepared as a by product in the manufacture of superphosphate fertilizers. Discusses the relationship between radium concentration and gamma-ray dose rate
Reviews literature on radioactivity in construction material. Finds that radioactivity in building materials used in the United States has received very little attention and that except for studies to find construction materials of very low background, there are no reports of radiological surveys of any U.S. building materials used for general construction purposes. Discusses surveys made outside the U.S.A. and summarized the gamma exposure rates found inside buildings (table 2). Gives bibliography of approximately 270 references.
Login