Discusses actual ventilation rates in small houses and the requirements of Swedish building regulations. States that regulations do not take a total view of the energy balance in small houses, and pay no regard to the interplay between different forces.< Discusses a newly built 1.5 storey house as an example. Outlines problems in ensuring a low air change rate.
Describes the basic relation between pressure difference and air flow rate across an opening under steady state conditions. Taking the ventilation system into account, the pressure difference pattern across building enclosures andthe air leakage characteristics of exterior walls, interior separations and various service shafts must be understood, but at present little of this information has been available for actual buildings. Presents new data on the air leakage characteristics and natural ventilation rates for sound insulating houses.
Contains two papers reprinted from the Jnl. of Ind. Aerodynamics:-< 1) Wind-tunnel simulation of the adiabatic atmospheric boundary layer by roughess, barrier and mixing-device methods.< Discusses the philosophy of roughness, barrier and mixing-device simulation methods. Illustrates methods by measurements of simulations in the B.R.E.boundary layer wind tunnel.
Gives results of a survey carried out in December 1978 on heating and ventilating of dwellings. 2000 men and women were questioned throughout the federal republic. Gives range of dwellings, desired and actual room temperatures, types of windows, frequency and duration-of window opening and the existence of draughts.< Concludes inter alia that heat loss through ventilation is greater than commonly assumed. In particular this heat loss is through leaky windows and ventilated bedrooms.
Discusses mechanisms for radon liberation in dwellings. Mentions survey which found radon concentrations exceeding the maximum permissable concentration of 3 x 10^-12 curies in 13 of the 65 dwellings. Gives expressions for number of radon atoms in indoor air at time t and activity due to radon per unit volume. Discusses liberation of radon from walls and from soil and concludes that if the ventilation is poor or if there is a high emanation of radon, the indoor radon concentration may approach the maximum permissable level.
Reports study of emanation of radon from concrete blocks enriched with uranium ore, placed in an airtight enclosure. The radioactivity of air samples was determined using a high resolution silicon diode detector system.
Reports study of the exposure rate due to the gamma-ray natural background in some representative areas of Italy using a portable high-pressure ionization chamber. In some areas spectrometric measurements were made to distinguish between contributions to the total from cosmic rays and from natural radioactive series. The measurement areas were chosen to be representative of the main geological formations.
Reports environmental background radiation exposure measurements made in approximately 100 residences in the vicinity of Livermore, California showing variations in annual exposure from 52 to 130 mr. Measurements were made with CaF2:Dy (tld-200) dosimeters at quarterly intervals for a period of 1 year. Dwellings were typically wood-frame structures with stucco exteriors. Interior exposure rates were, on average, about 25% lower than those outdoors.
Points out that conservation measures such as storm windows which seal a building protect occupants from outdoor air pollution but amplify effects of pollution generated indoors. Considers which effect is greater. Develops a model relating indoor air pollutant concentrations to outdoor concentrations and to v, the air exchange rate, which is consistent with reported behaviour of common pollutants. Model predicts that indoor concentrations follow outdoor concentrations but maxima and minima lag behind, and are not as pronounced as theiroutdoor counterparts.
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