English

Discusses masonry walls in relation to the air tightness of buildings. Considers mainly panel walls constructed of concrete blocks. States that in general such walls are very leaky, due mainly to shrinkage of the wall itself and deformation of the surrounding structure. Discusses the addition of insulation to wall, sealing of joints around window frames and at the edge of the floor slab. Gives diagrams showing details of building construction.

Discusses indoor air quality in residences with low ventilation rates. Reports investigation of indoor air pollutant levels in a test kitchen with a gas stove under various air change rates. Results indicate that gas stoves generate high emissions of carbon monoxide, nitric oxide, nitrogen dioxide, formaldehyde and respirable aerosols. Recommends a kitchen ventilation rate of at least 170 cu.m.&h.< Also reports study of CO and NO2 emissions from gas appliances in an energy- efficient research house.

Presents a technique using fan pressurization results and weather data to calculate infiltration. The geometry, leakage distribution, and terrain and shielding classes are combined into two reduced parameters which allow direct comparison of wind-induced and temperature-induced infiltration. Using these two parameters and the total leakage area of the structure (found from fan pressurization) the infiltration can be calculated for any weather condition. Presents experimental results from 15 different sites for comparison with theoretical predictions.

Considers the characteristics of flow through small gaps. Discusses relation between wind tunnel measurements and actual wind pressure on buildings and the effect of building shape on ventilation. Derives equations for flow rate through a gap for different temperature and pressure differences and sizes of gap. The equations consider the pressure as a function of time thus modelling the effects of a turbulent wind incident on a gap.

Presents a simple model for the calculation of wind induced ventilation. The model requires as input, pressure coefficient data, wind direction, and the open areas for each element of the building. Gives an example of the model applied to a model livestock building. Gives flow chart and listing of computer program. Note model does not include temperature effects.

Discusses the mechanisms of natural ventilation. Gives equations for stack effect and ventilation due to wind. Discusses use of natural ventilation in livestock buildings. Shows how minimum and maximum ventilation rates for winter housed cattle can be calculated using physiological data and a model for calculating the critical temperatures. Gives sample calculation of the ventilation rate necessary for beef cattle housed in a 9m. wide building.

The open ridge is a ventilator commonly used in cattle buildings. Reviews literature on the open ridge. Finds that there is outright disagreement between the sources referenced. Describes wind tunnel study to show whether or not the ridge design could influence the pressure coefficients when subject to wind. Finds there is no practical difference in pressure coefficients generated at the ridge of a building whether there are no upstands, upstands alone or with caps. For a 0deg.

Measurements have been made of the air-leakage rates through structural components of conventional metal-panel and concrete buildings which may serve as containment for nuclear reactors. The component measurements included structural penetrations such as doors and louvers as well as materials such as caulking compounds, gaskets, and paints. Specimens were sealed inside of test vessels.

Reports methods used to measure the concentrations of Rn, Tn, and their decay products indoors and outdoors. Radon and Thoron concentrations are detected continuously by collecting the positively charged RaA and ThA atoms on a surface-barrier detector using electric field precipitation.< The concentrations of Radon and Thoron decay products were determined by collecting them on a membrane filter and simultaneously counting the activities by means of a collimated surface-barrier detector.Indoor and outdoor concentrations are measured simultaneously under different ventilation rates.

Reports tests of a scintillation counter to detect Ra 222 in air and water. The counter consists of a spherical cavity coated with ZnS(Ag) powder, built in a lucite cylinder whose external surfaces, excepting the window which is put in contact with a photomultiplier, are made reflective with a special paint. The performance of the detector has been analysed with respect to size,efficiency, background, constant activity and constant concentration in the sample. Finds that for liquid samples, two different values for the diameter, 5 cm. and 7.5 cm.