health

The determination of an acceptable range of humidity is complicated by the conflicting effects of an increase or decrease in humidity levels on the speed of chemical interactions and growth of biological organisms and pathogens that may affect human health and comfort.

The aim of the present study is to measure the possible health effects among tenants after certain characteristic energy conservation measures had been taken in their dwellings. Changes in comfort are also included. It is part of a number of projects on subjects such as indoor pollutant source control and changes in house dust mite populations related to moisture changes in retrofitted dwellings.

Notes the contaminants which may be contained in room air - radon, solvents, tobacco smoke, formaldehyde, dust mites etc. Points out that no definitive threshold values have been established for contaminants representing health hazards. Points out that the reactions of various individuals to them differ widely, determined by a number of factors.

Reviews current knowledge about the sources of a number of indoor pollutants and their concentrations: tobacco smoke, NO2, CO, radon, formaldehyde, SO2, CO2, O3, asbestos, mineral fibres, organics and allergens. Lists the adverse health effects from exposure to each of the pollutants. Finds instrumentation for measuring exposure acceptable, but monitoring and knowledge of distribution of sources and concentrations inadequate or marginal. Knowledge of exposure-effects relationship is inadequate, especially with regard to delayed effects of chronic exposures.

In addition to air quality problems encountered in other sealed buildings, both workers and patients in hospitals may be exposed to very special air contaminant problems. Levels and ranges of a variety of chemical pollutants measured in 16 h

Examines evidence for relating sickness to the office environment. Notes research into the office building syndrome (obs) in various countries. Notes that although air conditioning goes back to the 1920s, obs has been in the news only during the last five years or so. Notes the contribution to this of energy saving regulations. Notes the complex nature of indoor air contamination. Points to obvious factors such as air conditioning systems unserviced for 30 years, occupational psychology, indoor architecture, climatic constance and air ionisation.

As our understanding of human exposure to air pollutants improves, it is becoming increasingly evident that indoor environments play a critical role in determining exposures. However, it is not possible at the present time toestablish the relative contribution of indoor and outdoor sources to personal exposures, nor can the contribution of specific indoor emissions be quantified. To address these issues, a chamber experiment was initiated to measure particulate and organic emissions from important indoor sources.

Reduction of fresh air ventilation is becoming the major means of energy conservation in office buildings. Simultaneously, health and comfort problems experienced by occupants are often suspected to be a direct result of reduced fresh air ventilation. However, there is little data available on health and comfort problems experienced by occupants of buildings operated under normal ventilation rates.

Possible health effects and changes in sensation of comfort among tenants after replacement of single glass windows in leaky frames with double glass windows in airtight frames have been studied. The study design was observational, and included a study group and a corresponding control group. The results indicate essential improvements of the indoor climate and of the health status of the tenants after replacement of the windows (i.e.

One option of reducing residential energy consumption is to improve air tightness but adequate ventilation must be provided for health reasons. Sources of infiltration and factors affecting infiltration rates are described, with methods for quantifying and comparing rates. The relationship with air quality is explained and the effect that air quality has on respiration and health. Typical indoor pollutants are carbon monoxide, carbon dioxide, nitrogen oxides, radon and radon progeny, formaldehyde gas, particulates, tobacco smoke and odours.