Radon and ventilation - Radon och ventilation

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.

Instrumenting energy audits.

Discusses ways of increasing accuracy and thoroughness of energy audits of buildings by use of specialized instruments and improved audit techniques. States air infiltration measurements are key item in audit procedure. Describes 'house doctor' kitwhich with records of past energy usage, knowledge of prevailing weather and a questionnaire are used to establish the energy signature of a house. The kit includes blower door, infrared camera, temperature probes and appliance consumption meter. Describes simple tracer gas method using sulphur hexafluoride collected in sample bottles.

Ventilation : the human factors

Gives state-of-the-art review of ventilation needed to control carbon dioxide, odours, cigarette smoke and moisture mentioning main results. Gives sketch graphs illustrating these results. Outlines the effect of opening windows on air -change-rates andgives tables showing average window opening, the moisture generation from various activities and the solar radiation falling on vertical surfaces.

Retrofitting : plan action and early results using the townhouses at Twin Rivers

Describes plan to retrofit 25 townhouses at Twin Rivers evaluating retrofits by instrumenting each house to record energy consumption, temperature, window and door opening and furnace operation. Aim of the first round of retrofits was a payback period of no more than three years. Describes fourretrofits A,B,C and D. A,C and D improved attic and cellar insulation and insulated the heating system. B aimed to limitthe amount of air infiltration from cracks around doors and windows by weatherstripping. Early results showed gas savings of the order of 25% and electrical savings of 10%

Ventilation with open windows

Shows need for intermittent high ventilation in dwellings to remove water vapour and odours. Suggests openable windows as the simplest and most common method of ventilation control. Gives air-change-rates in two british houses using carbon dioxide andnitrous oxide as tracer gases, showing the effect of opening windows. Shows that increase in ventilation rate caused by opening windows can be tenfold and is not confined to the room with the open window. Closing of internal doors has a significant effect. Describes investigation of air flow within rooms using smoke.

Condensation risk and improved thermal performance of housing.

Considers the likely impact of alternative conservation measures on the incidence of surface and interstitial condensation on or within the elements of the building fabric. Considers specifically domestic buildings in temperate climates such as in the U.K. and Ireland. Outlines the mechanisms whereby condensation occurs and considers broadly the effect of reducing heating levels, reducing ventilation and increasing insulation.

Ventilation and air infiltration in buildings.

Briefly outlines the approach used and the results obtained by computer modelling in estimating the magnitude of natural ventilation in irish housing. Concludes that in general air-change-rates in irish housing are excessive.

Sulphur hexafluoride as a gas-air tracer.

Give method for collecting and analysing sulphur hexafluoride used as a tracer gas. The gas is separated by gas chromatography from other components of moist air on columns of silica gel and activated carbon in series and is detected by electron-capture analysis in concentrations near 1 p.p.b. states that sensitivity can be enhanced at least 2000-fold by freeze-out concentration. States that SF6 backgrounds in air are undetectable except near leakage sources such as transformers.

Ventilation requirements in rooms occupied by smokers: a review.

States that the need for fresh air to dilute cigarette smoke is the dominant criterion for ventilation design. Reviews the literature of the subject and concludes that the three main health factors are carbon monoxide, acrolein and particulate matter. Finds very wide differences in sensitivity between people. compares IHVE guide of 1970 with the british standard draft code of practice CP3 concludes that cigarette smoke shouldbe treated as a contaminant and not linked with body odour dilution.

The ionizing radiation in dwellings related to the building materials.

Reports measurements in seven groups of town house in Gavle, Sweden of concentrations of radon and daughter products. Gives results with the type of building materials, the ventilation systems and air-change rates measured using nitrous oxide as a tracer gas. Gives formula for the permitted limits of radionucleides in building materials. Discussed results and concludes that the concentration of radon does not differ significantly from single family to multi-family houses.