English

Heating systems may emit pollutants into living spaces of buildings. Presents model for estimating exposure to pollutants allowing for variation of air change rate and inside-outside temperature differences. Examines the effect of energy conservation measures. Concludes that if ventilation alone is reduced the pollutant concentrations will rise but if reduced ventilation is balanced by increased insulation then pollutant contributions will remain unchanged. The analysis applies only to pollutants generated by the heating system.

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

Reports results of measurements of the environmental radiation inside Norwegian houses. Three types of measuring equipment were used: a scintillation rate meter specially designed for low intensity measurement, a geiger counter with a rate meter, and an ionisation chamber. The average doserate in air due to environmental radiation was found to be 87 mrad/year insidehouses with outer walls of wood. 115 mrad/year for buildings with outer walls of concrete and 129 mrad/year for buildings with outer walls of brick.

Points out that conservation measures such as storm windows which seal a building protect occupants from outdoor air pollution but amplify effects of pollution generated indoors. Considers which effect is greater. Develops a model relating indoor air pollutant concentrations to outdoor concentrations and to v, the air exchange rate, which is consistent with reported behaviour of common pollutants. Model predicts that indoor concentrations follow outdoor concentrations but maxima and minima lag behind, and are not as pronounced as theiroutdoor counterparts.

Reports environmental background radiation exposure measurements made in approximately 100 residences in the vicinity of Livermore, California showing variations in annual exposure from 52 to 130 mr. Measurements were made with CaF2:Dy (tld-200) dosimeters at quarterly intervals for a period of 1 year. Dwellings were typically wood-frame structures with stucco exteriors. Interior exposure rates were, on average, about 25% lower than those outdoors.

Reports study of the exposure rate due to the gamma-ray natural background in some representative areas of Italy using a portable high-pressure ionization chamber. In some areas spectrometric measurements were made to distinguish between contributions to the total from cosmic rays and from natural radioactive series. The measurement areas were chosen to be representative of the main geological formations.

Reports study of emanation of radon from concrete blocks enriched with uranium ore, placed in an airtight enclosure. The radioactivity of air samples was determined using a high resolution silicon diode detector system.

Contains two papers reprinted from the Jnl. of Ind. Aerodynamics:-< 1) Wind-tunnel simulation of the adiabatic atmospheric boundary layer by roughess, barrier and mixing-device methods.< Discusses the philosophy of roughness, barrier and mixing-device simulation methods. Illustrates methods by measurements of simulations in the B.R.E.boundary layer wind tunnel.

Describes tests in Exeter University library of method of determining ventilation rate by measuring the amount that the atmospheric carbon dioxide concentration in an occupied space is raised above the outside ambient level. Compares rate obtained with that expected from the fan rating. Demonstrates that in addition to the ventilation rate, the average rate of production of carbon dioxide produced by the occupants could in principle have been estimated from the data.

Uses Turk's equation to obtain CO concentration v time curves in an office and a one-family house. Compares results with similar studies, current threshold limit values and ambient air quality standards for CO. Finds model is apparently valid for CO and probably for other gaseous contaminants not affected by absorption or deposition. Concludes that commercial environments should have at least 5 cfm fresh air per occupant and that a value of 50 cfmfresh air appears to be adequate for a one-family dwelling.