English

The indoor air quality of five detached dwellings, two townhouses, six apartment units, two mobile homes, one school and one hospital have been monitored. The pollutants monitored were CO, NO, NO2, SO2, O3, CH4, CO2 and total hydrocarbons. Reports results and describes a mathematical model developed to predict indoor concentrations of these pollutants. Briefly discusses the effect of energy conserving measures on indoor air pollution.

Briefly reviews factors to be taken into account in considering natural ventilation in commercial and industrial buildings. These factors include the location of the building, surrounding buildings, activity within the building and results required of the installation. Notes some of the problems andpossible advantages of combining natural and fan powered systems.

Indoor concentrations of pollutants often equal or exceed outdoor concentrations, and since most people spend 90% of their time indoors this constitutes a health threat much greater than that posed by outdoor pollution, which has received most of the attention in the U.S.A. The problem has been made worse by energy conservation measures which reduce ventilation. Thisarticle reviews recent research findings and their implications for pollution control programmes, and considers the further research that is needed.

Assesses the role of natural ventilation in modern hospitals. Considers optimum standards of air change rates for winter and summer conditions and reviews factors within the hospital context that are likely to affect the achievement of natural ventilation. Notes an air change rate of 1.5/hr. is usually assumed for heat loss calculation. Finds cross ventilation is unlikely to be achieved and designs should be based on single sided ventilation. Reports tracer gas measurements of natural ventilation in Southland Hospital, Shoreham by Sea.

Reports measurements of air leakage in several supermarkets and an enclosed shopping mall, all constructed between 1954 and 1979. All tests were conducted by using a large fan to depressurize the building. Gives graphs of leakage rates. Finds supermarkets are two to four times leakier than schools or high-rise office buildings.

Presents a new method for determining the airborne concentrations of RaA, RaB and RaC in atmospheres contaminated with radon-222. The method employs alpha spectroscopy to measure the count rates of RaA and RaC' present on a membrane filter sample at two post-sampling times. The individual air concentrations and the statistical variances associated with each may then be calculated from the equations given. Presents theoretical and experimental comparisons which indicate the improved accuracy of the spectroscopic method over methods previously available.

Gives results of a statistical survey of energy consumption in British government buildings. Suggests one reason for high consumption may be excessive ventilation. Reports field trial of the effect of reducing natural ventilation in a London office building. Window frames were sealed with a rubber mastic, giving an annual fuel saving of 22%. Finds measure was highly cost effective with a payback period of less than three years.< Discusses problem of heat loss through large doors in hangars and workshops.

With increased concern for energy conservation, many new standards have been developed. Discusses these standards which are of three types, prescriptive, component performance and performance. Outlines several design approaches toreducing air infiltration.

Discusses flow of air between two rooms through an open door. Considers 6 cases with and without mechanical ventilation and with a temperature difference between the two rooms. Gives examples of the calculation of air flow. Recommends that for hospitals where the transfer of bacteria should be avoided, doors should be kept shut as much as possible and that it is not economically justifiable to choose such a high ventilation rate that no undesirable back flow occurs with the doors open.

Four two-storey four-bedroom test houses were built in 1974 near Columbus, Ohio and have been instrumented and monitored by Ohio State University. All four houses are unoccupied. Air infiltration rates were measured in all four houses using sulphur hexafluoride as a tracer gas and two of the houses were pressure tested for air leakage. Discusses results and the correlation between infiltration, inside-outside temperature difference and wind velocity. Compares tracer gas results with pressurization tests.