This paper extends an earlier investigation of scale effects on buoyancy driven recirculating flows in stairwells of the kind adopted in domestic accommodation. Further consideration is given to the role of Reynolds number, which proves to have unexpected features, possibly because stairwell flows fall into the range of incipient instability. A technique is developed to introduce explicitly the fraction defining the way in which the energy loss from the system is divided between the regions above and below the stairway.

Three thermal analysis methods with different degrees of empiricism are quantitatively investigated regarding the ease of use, efficiency, accuracy and redundancy of generated information. From this investigation it is concluded that, for design purposes, a sensitive interplay between experiment and theory can often lead to an optimum method. 

Selected articles on the subject of indoor air quality.

The average UK household spends about +500 per year on heating, lighting and power for domestic appliances but there is a huge variation between individual household expenditures. Field trials, in which the energy use in occupied dwellings is measured, show that the physical characteristics of the dwelling and the lifestyles of the occupants are about equally important in determining energy consumption. It is clear, therefore, that realistic estimates of domestic energy consumption can only be made if both these factors are considered together.

A simple model is developed for the estimation of annual rates in single-family houses using indicators for both house tightness (air changes at 50 Pa) and site climate (the leakage-infiltration ratio). This technique is best suited to low-accuracy, large data set problems where detailed data are not available. The method is similar to the method attributed to Kronvall and Persily (ie, the K-P method), but is derived from a physical model, the LBL infiltration model.

This overview explains why indoor air quality (lAQ) has recently attracted so much attention what are the major sources of indoor air pollution, and what are the health effects of concern. It discusses differences among occupational, outdoor, and indoor air pollution problems including some of the different measurement needs. It also covers the total exposure concept, and discusses the California IAQ Program. Emerging trends in indoor air quality measurement techniques are presented in the final part of the paper.