English

The multiple tracer gas technique of I'Anson et al. has been improved, in order to increase the rate at which samples can be taken. Using parallel gas chromatographic separation columns and an electron capture detector, it is now possible to take an air/tracer gas sample every thirty seconds in the case of a two-zone ventilation and air movement test. Rapid sampling enables a new,simplified analysis of the air movement between two connected zones to be employed. This analysis derives ventilation rates and intercell airflows simultaneously.

A large proportion of heated rooms depend primarily on natural convection for the distribution of heat within the occupied zone. A method of predicting air temperature variations with height is presented. Using the heat and mass flow rates of the driving convection plume, along with the corresponding parameters of downward flowing air streams at cool surfaces, an estimation of the maximum (upper) temperature and the minimum (lower) temperature can be made. Incoming air entry points can also be taken into account.

Explains the principles involved in condensation and the conditions producing condensation, both atmospheric and other sources of moisture. The behaviour of absorbent materials and surfaces is described. Interstitial condensation is explained. Designing to avoid condensation, taking account of the characteristics of the building fabric and the environment, is necessary. A worked example of estimating condensation risk is given.

Reports results of studies of concentrations of carbon monoxide, nitrogen dioxide, respirable suspended particulate matter and volatile hydrocarbons in houses in the Netherlands. Carbon monoxide and nitrogen dioxide were studied in about 300 homes in Arnhem and Enschede in October-December 1980. Respirable suspended particulate matter, nitrogen dioxide and volatile hydrocarbons were measured in 175 houses in Ede in winter 1981-82. Indoor air pollution was often much higher than the common outdoor levels. In several houses existing or proposed standards for ambient air were exceeded.

Describes the influence of gas geisers on carbon monoxide and nitrogen dioxide production in 254 houses in the Netherlands. It was shown that burner type and maintenance system were the main factors influencing the carbon monoxide levels in the flue gases. The nitrogen dioxide concentration in the kitchen was greatly influenced by the presence of a flue for the geiser and by use of a cooker hood. Associations were also found with type of space heating, use of shower and socioeconomic status of the occupants.

Discusses sources of nitrogen dioxide in indoor air in houses in the Netherlands. Measurements were made in a random sample of about 300 houses with a geiser in Enschede and Arnhem. A second sample of 326 houses in Ede were measured a year later. The Dutch outdoor standard for concentrations of nitrogen dioxide was regularly exceeded indoors.

The influence of indoor nitrogen dioxide exposure on respiratory symptoms of school children was investigated in a case-control study. The election method used was useful in obtaining symptomatic children, but insufficient indefining cases and controls without additional information. No relationship between indoor NO2 and respiratory symptoms was found. Bias may have been present, especially because of the high mobility of the study population. Attempts to estimate historical exposure were inaccurate.

A small, personal monitoring study was performed in a subpopulation (14 families) of a case-control study on the relationship between indoor nitrogen dioxide exposure and respiratory diseases of school children. 

Indoor NO2 concentrations were measured in the kitchen, the living room and bedroom of 612 houses in two different areas in the Netherlands. In asub-sample, personal exposure of the housewives to NO2 was measured. NO2concentrations indoors depended on the presence or absence of (un)vented gas appliances. Personal NO2 exposure was only different between the two areas in the group with the lowest indoor concentrations. It was concluded that with respect to NO2 exposure it is impossible to categorize groups without accounting for gas appliances inside the house.