Describes in detail a multi-cell model for predicting ventilating airflows. Gives equations for flow through cracks, wind and stack effect. States that comparisons between prediction and measurements indicate that the method is capable of giving relatively high accuracy for a wide range of ventilation conditions. Discusses advantages and disadvantages of multi-cell and single-cell methods. Argues that multi-cell approach is potentially more accurate and more useful.

Describes computer program developed by BSRIA to predict ventilation rates and directions of air flow in buildings for given sets of conditions. These conditions are wind speed and direction, temperature differences between inside and outside the building, air leakage characteristics of the components and the mechanically induced air flow rates. The report is in the form of anoperating manual for the program.

Describes investigation of the effects of five hour exposure of sixteen young people to different concentrations of formaldehyde. Physiological parameters, subjective discomfort and performance were monitored. Discusses setting of exposure standards for formaldehyde and suggests standard of 0.15 mg/m^3 for continuous exposure.< Discussion includes an account by R.Baars of developments in the Netherlands and measures taken to reduce formaldehyde concentrations in dwellings.

An air to air heat exchanger is only of value if one can control the movement of air into and out of the house. Suggests measures for reducing air leakage. describes construction of an air to air heat exchanger. Finds that heat exchanger can be used to control humidity in houses. Suggests use of a solar collector to preheat the cold outside air entering the heat exchanger.

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.

Describes air infiltration measurements made in three apartment houses in the Chicago area using SF6 as a tracer gas. Two were in tenement districts and one was suburban. Data were collected in selected apartments in each building, and these data were used to estimate the infiltration rate for the entire building.

The Swedish building regulations give recommended tightness values for buildings of 3 air changes per hour for single houses, 2 air changes per hour for other housing with not more than two stories and 1 air change per hour fortaller buildings.

Describes sources of radon in materials and measures of exposure. Reviews measurements of radon in mines and dwellings. Describes measurements of the concentration of radon in a sealed chamber. Concludes that concentration of radon daughters can be reduced by removing dust from the air using an electrostatic precipitator or by using a very high ventilation rate combined with an efficient heat exchanger. Finds most significant sources of radon in dwellings are cracks and openings in the floor. Suggests reducing radon by covering bare surfaces and sealing the floor, or using a crawl space.

Reports research undertaken to find the effect of a continuous sheathing board and skirting on the infiltration rate in a mobile home. Two mobile homes were tested, one equipped with sheathing board, and one caulked at structural joints. 

Reviews past research in air infiltration, discussing various models. Proposes research agenda. Gives anotated bibliography. Describes commercial and residential models. Gives test results and a summary of the models.