health

Air pollution from combustion of fossil fuels can be injurious to health causing damages to air passages. Discusses health risks caused by radon emission in houses. Tables illustrate expected effects of exposure todifferent pollutants, causes of death, 15 years cumulative mortality data, mortality distribution comparison between UK and Sweden, risk of lung cancer caused by radon exposure, and effects on health caused by energy saving methods.

Notes one of the principal ways in which members of the public receive natural irradiation is by breathing the decay products of radon 222. Reviews data on radiation exposure and the incidence of cancer for uranium miners. Discusses uncertainties and inadequacies in the data. Gives estimates for the incidence of lung cancer in the general public, caused by radon exposure.

Reports some results of field measurements of radon levels in apartments and houses and shows that summer measurements with high natural ventilation rates are generally lower than winter measurements. Suggests exhalation of radon from building materials can be studied by placing samples of material in closed vessels and following the growth of activity in the vessels. Shows that a ventilation rate of one air change per hour will lower the theoretical maximum level to 0.008 of the unventilated maximum value.

Radon is a radioactive gas which diffuses naturally from all mineral based building materials. States for most homes, concentration of radon is approximately inversely proportional to the ventilation, although this is not valid for very low or very high air change rates. Gives brief results of measurements of concentration of radon in dwellings. Outlines health risks from radon and daughters. Reviews norms laid down in some countries for specific situations. Discusses ways of reducing radon concentrations.

Reports findings of a working group on health aspects related to indoor air quality. Identifies main air pollutants generated both outdoors and indoors. Considers adverse health effects of indoor pollutants. Concludes that ventilation rate is the important factor in the health concerns discussed. Finds a lack of valid health data on the indoor climate. Recommends further studies.

With improved thermal protection of buildings proportion of ventilation heat loss has grown until it now accounts for 50% and more of total building heat losses. Since ventilation cannot be reduced below certain limits for comfort and hygenic reasons, selection of appropriate type of ventilation system is increasingly important to control heat losses. Describes characteristics and consequences for heat energy consumption and hygiene of constant ventilation and abruptly increased ventilation such as window opening etc.

Describes background to natural radiation in building materials and particular aspects of radium decay which produces radon. Notes human lung capacity to absorb airborne particles and associated health risks. Illustrates diagramatically different particle sizes retained in various sections of human respiratory system. Suggests methods to avoid exposure to decay products: avoid materials with high radium content and maintain low radon concentration through sufficient ventilation. Graph shows concentration of radon in relation to air change rate.

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.

Discusses toxic and flammable gases and vapours that lead to hazards in buildings. Examines trends in accidental deaths in the home in England and Wales from gas poisoning. Discusses influence of buoyancy on the dilution by ventilation air of accidental leaks of toxic and flammable gases and shows where buoyancy dominates layers can readily form. Presents theoretical results for controlling gas hazards in buildings by ventilation for a wide range of practical situations.

Notes that reduced infiltration and ventilation rates in buildings can lead to higher levels of indoor air pollution. Discusses three indoor-generated pollutants : nitrogen dioxide, formaldehyde and radon. Suggest ways of circumventing increased health risks without compromising energy conservation considerations, including setting standards for minimum levels, filtering recirculated air and sealing source material.