radon

The simple steady state model which is frequently used to relate radon concentration (C), source strength (S) and ventilation rate (l/tau) is expressed in the equation C=S tau. The assumptions of this model are given and their validity explor

The general principles and mechanism of how soil gas infiltrates and carries radon from the foundation bed and subsoil into buildings are discussed. The Swedish Building Research Council has funded experiments and evaluation of cost effective remedial actions. The work has concerned existing dwellings with high concentration of radon, resulting from infiltrating soil gas and/or exhalation from building materials. A review and evaluation is given of experience and results acquired up to the summer of 1984.

As part of a comprehensive indoor air quality and infiltration field study, radon concentrations were measured in 60 houses in upstate New York using passive integrating monitors. Indoor air radon concentrations ranged from 0.2 pCi/1 to 50 pCi/1. Four houses with the highest radon levels were then extensively monitored using real-time continuous instruments for the measurement of radon, radon daughters, respirable particles, infiltration, inside-outside pressure difference, and weather parameters.

Plastic track detectors LR-115 and CR-39 were used to estimate the concentration of radon-222 and its daughter products (218Po, 214Po) in a room by recording tracks of their alpha-particles. Although the ventilation rate is the main factor th

Complaints related to moisture problems in houses which had been air sealed, led to a study of indoor air quality in 20 weatherized demonstration homes in the Cambridge, Ontario area. 

Indoor radon concentrations have been measured in a 13 year old two story concrete building of the University of Texas at Dallas. Variations of the radon concentration from the basement to the second floor in offices, classrooms, laboratories, storage rooms, corridors and other locations have been measured. Dependence of the above concentrations on the location and ventilation rates have been studied.

The largest contribution to population exposure from natural radiation arises from the inhalation of the decay products of radon in indoor air. In most instances the dominant source of radon within buildings is the subjacent ground. However, building materials do contribute to the radon concentration in indoor air, and in some circumstances may provide the major source. Thisreport reviews some of the literature on radon emanation from soils and building materials world-wide.

Reducing the air change rate of a house increases the concentration of pollutants in the indoor air. These pollutants are identified and located within the residential structure. Air-to-air heat exchangers are suggested tocontrol ventilation, and the three basic types described.

Indoor air quality sampling strategies and analytical techniques have changed significantly in the past ten years. The changes reflect both the shifts in study objectives and the development of new forms of instrumentation. Toillustrate these trends, this paper describes early field techniques for measuring indoor air quality using a heavily instrumented mobile laboratory that is suitable for measuring one building intensively for up to four weeks.The style of measurement now is complemented by large field survey projects using passive samplers as the dominant instrumentation.

A pilot study was conducted using workers from a semiconductor plant. Describes the methods used to acquire and evaluate air pollution exposure data for significant environments (including workplace, in-transit, and residence) to which workers are exposed throughout a typical 24-hour day. Summer andwinter measurements were made on products of combustion, radon, respirable particulates, and a variety of organic compounds including methylene chloride.