Discusses the mechanisms which govern natural ventilation. These are wind speed, flow, characteristics of openings in buildings and pressures generated at building surfaces by wind and temperature difference. Gives formulae for simple cases. Outlines ways of determining natural ventilation rates. Gives brief account of the effect of turbulence and openings in one wall only.

Discusses fresh air requirements and tolerable levels of contamination from various sources within a space. Explains the calculation of dilution rates. States that in summer the rates required will generally be higher than those derived from theinformation given because of the need to reduce temperatures in non-air-conditioned buildings and gives method for calculation of ventilation rate required.

Reports measurements in seven groups of town house in Gavle, Sweden of concentrations of radon and daughter products. Gives results with the type of building materials, the ventilation systems and air-change rates measured using nitrous oxide as a tracer gas. Gives formula for the permitted limits of radionucleides in building materials. Discussed results and concludes that the concentration of radon does not differ significantly from single family to multi-family houses.

Describes a research project undertaken at the Building Research Station to measure wind pressures on the G.P.O. tower, London, and dynamic strains in the tower shaft. The development of a suitable pressure transducer which used strain gauges as sensors is described, together with the installation at the tower. some othe problems of strain gauging large civil engineering structures are outlined. NOTE Final results of this project are given in "Wind pressure and strain measurements at the Post Office Tower" Newberry C.W. Eaton K.J. Mayne J.R. abstract no.229. B.R.E. C.P. 30/73

Discusses variations in the test results which occur with the laboratory procedures for assessing the air and water penetration attributes of windows. Presents data for windows examined under British Standard BS 4315 : part 1 "Methods of test for resistance to air and water penetration - windows and gasket glazing systems". Considers the implications of thesetests for the development of performance levels for use in standards and procurement documents, and proposes a two-stage statistical procedure, based in the first instance on tests on five windows.

Presents some results not previously published of the full-scale loading project carried out at the post office tower, London. Autocorrelations and pressure spectra were determined for all the pressure transducers, and the variations of these around thestructure as well as vertically are discussed.

Reports results of surface wind pressure measurements made simultaneously at thirty-two points on a 57-storey office tower in Toronto. In addition to readings taken at half-second intervals during high winds, mean and root-mean square pressures were recorded for a five-minute interval once each hour, and pressure coefficients referred to the free stream dynamic pressure at 286 m were computed for comparision with wind tunneltest information.

Presents method for collecting air infiltration data in a large sample of dwellings. The method consists of a tracer gas dilution technique using sulphur hexafluoride and employing air sample bags which are analyzed in a central laboratory. Themethod is easy to perform and inexpensive and will be used in approximately 300 dwellings on 16 sites to give air exchange rates under typical heating season conditions. Presents preliminary data on air infiltration rates in low-income housing in Portland, Maine.

Describes the philosophy and formulation of the simple and detailed procedures for wind loading of the Canadian National Building Code of 1970. Defines design pressure in terms of the exposure of the building, its response to gusts, the mean velocity pressure and the structural shape of the building. Compares predictions of dynamic drag response and cladding pressures with full scale measurements on several tall buildings. Concludes that the predictions of drag response and windward pressure are satisfactory. Discusses area requiring further definition.

Describes adaptation of photo-electrical optical technique to measure ventilation rates in wind tunnel models. Illustrates probe photographically and diagrammatically. It comprises essentially a light-emitting diode and a hybrid photodiode-amplifier detector. Compares technique with conventional tracer gas technique using helium and a katharometer and finds good agreement. Considers optical probe has considerable potential for measurements in small and multi-celled models where conventional techniques are not feasible.