The work to be described here is an elaboration of Lehmberg's preliminary experiments. The object was to study the general problem of ventilation odours under normal conditions, comparable to those in schoolrooms, offices, homes and the like with the possibility of establishing ventilation requirements for various groups of individuals, including grade school children and adults, under representative winter and summer conditions. Three methods of odor control were studied dealing with personal sanitation, ventilation, and air washing.
One important factor in the spread of airborne infection must be the movement of the air itself i.e. the ventilation, although an exact correlation of it with the risk of infection has yet to be found. As part of an infection survey in a hospital ward we made a detailed study by physical methods of the movements of the air and of the transport of particles by this means. A description is given of the methods employed.
In this paper it is our intention to consider that ventilation is the circulation or passage of an air supply through an enclosure resulting in the displacement of some or all of the air contained in that enclosure by thesupply air. Depending on the character and condition of the supply air it can dilute or change the quality of the air in an enclosure as well as alter its temperature and humidity. A mathematical analysis of the ventilation process appears later in this paper.
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 cross sectional survey investigating building sickness was carried out in two buildings with similar populations of office workers but differing ventilation systems, one being fully air conditioned with humidification and the other naturally ventilated.
Summarizes a study reviewing indoor air pollution in housing in Canada. Concludes that 1, many materials and conditions which contribute significantly to indoor air pollution are known to be present in Canadian houses, 2,individual susceptibility to air pollution varies, 3, smoking remains a major source of pollution, 4, some energy conservation measures aggravate indoor pollution problems, 5, the full health, social and economic costs have yet tobe determined, and 6, acceptable levels of effects on health have not been defined.
The effect of reduced air infiltration rate caused by energy-saving measures has been studied by comparing the indoor climate in 25 sealed apartments with the conditions in 25 unsealed apartments in Denmark in four seasonal periods.
Compares the levels of possible cigarette smoke-related aerosols with the prevalence of health-related complaints in offices with different regulations about smoking, using data from two sources. The first was a review of 111 buildings with persistent building-related complaints and 32 buildings where there were no complaints. The second was a questionnaire completed by approximately 1100 employees from 9 buildings in New York City. The available data do not support a conclusion that increased reports of building-related complaints are associated with smoking.
Efforts to reduce the energy needs to heat or cool dwellings have the potential to create new health hazards. Increases in indoor levels of radon and its progeny from the reduction in air exchange rates add a substantial radioactive burden to the general population. Other indoor pollutants reaching critical concentrations in homes with low air exchange rates are CO and NO2 from unvented combustion in gas stoves and heaters, tobacco smoke, and asbestos fibres.
A two-part experimental study was conducted to identify antecedents of complaints from office workers in a sealed, air conditioned building. Building illness was documented as increased incidence of absenteeism and complaints among office workers in the study group compared to control subjects in a non-sealed building of a similar age. The second part monitored complaints and symptoms from subgroups when lighting was changed and when fresh air was introduced. Complaints and symptoms decreased with changes in air and lighting and increased again when previous conditions were established.