Based on current concerns regarding indoor air quality and energy use, there is a need for in situ techniques for evaluating buildings' infiltration and ventilation characteristics. The U.S. National Bureau of Standards has developed and employed equipment and techniques for such evaluation. The measurement of whole building leakage and ventilation rates has been reported on previously. Additional procedures are presented here for a more complete evaluation of the ventilation system operation and the distribution of air within the building.

As part of a programme to develop measurement methods for determining the ventilation rates of large buildings, we performed two series of tests in a single-celled laboratory with a volume of 600m3. The first series utilised constant concentration, constant emission and rate of decay tracer gas techniques to determine the characteristics of the infiltration pattern in varying winds and external temperatures. We used both discrete and continuous injection and sampling methods.

A survey is given of the sitution in The Netherlands with regard to ventilation and infiltration. Starting from a point of generally very leaky and hardly insulated buildings now the necessity is felt on the one side to make standards for the airtightness to prevent energy wastes by too high infiltration rates and on the other hand to define minimum ventilation rates to secure safe and hygienic conditions in well insulated and airtight buildings. This minimum ventilation rate is based on contaminants, caused by the occupants themselves, the so-called unavoidable sources.

Modelling houses as two coupled chambers, namely, the living area and basement, predicts more accurately the total indoor radon source flux from building materials and geology than a one-chamber model in houses with disparate radon concentration

Concentrations of airborne radon ranging from 0.05 to 135 pCi/L were found in houses in Maine. Track-etch cups were placed in five positions for 100 houses to determine integrated average radon concentrations over the period October 1980 - May

The indoor air of 60 residences in and around a Maryland suburb of Washington, DC, was monitored in a pilot study to determine residential radon concentrations. In each residence, a radon grab sample was acquired in the living room, and, if possible, in the basement. Infiltration rates were determined by tracer gas dilution. To help standardize sampling conditions, each home remained closed up for 8 hours prior to sampling and during analysis. Over 60% of the residences sampled showed air infiltration rates below 0.6 air changes per hour.

The expectation of elevated 222Rn levels in modern homes that have low air interchange rates with the outdoor air led to a survey of both conventional and solar homes in northeastern New York State. As a group, homes that are more airtight ha

Particulate and gaseous emissions from indoor combustion appliances.and smoking can elevate the indoor concentrations of various pollutants. Indoor pollutant concentrations resulting from operating one or several combustion appliances, or from sidestream tobacco smoke, were measured in a 27m3 environmental chamber under varying vent ilation rates. The combustion appliances investigated were gas-fired cooking stoves, unvemed kerosene--fi red space heaters, and unvented natural gas-fired space heaters. 

Ambient temperature may influence both the emission and the perception of human odour. This paper studies how human odour is perceived at different temperatures. 

Results from a two-box model for calculation of tracer gas concentrations in rooms are given and consequences of different definitions of ventilation efficiency are discussed. Results from three different series of experiments are presented.