English

An analysis has been made of draft failure with residential heating units operating at low rates of combustion during mild, calm weather. It has been shown that under these conditions the relation between chimney draft andhouse pressures becomes important in determining when venting failure will occur. A simple equation expressing this relation has been developed. It shows that draft failure will occur if the mean flue gas temperature in the chimney falls below a value that depends on the neutral zone level.

This article examines a solution procedure which can determine the flow in an air-conditioned room. The method is based on the solution of a group of equations for the flow (four non-linear partial differential equations) by means of a numerical method. Comparison with test results indicates that the method studied is suitable for prediction of air movement in an air-conditioned room when the flow is steady and two-dimensional. The method can be extended to give the required information for the evaluation of thermal comfort in the room.

Air pollution due to volatile compounds in six unoccupied houses with intended low energy consumption was measured. The measurements included air temperature, air humidity, ventilation rate and concentration of organic gases and vapours. On average 14 different compounds were identified in concentrations exceeding 0.005 mg/m3 in the samples, and Toluene and alpha-Pinene were the most frequent compounds. A total concentration of organic gases and vapours averaged for the five periods of measurements 0.46 mg/m3 (0.032 - 5.5 mg/m3).

Describes approach based on the Predicted Mean Vote concept as a suitable index of discomfort for housing with evaporative cooling. This index accounts for all important environmental factors and in addition allows dynamic modelling of human responses to the thermal environment, such as adjusting clothing levels and metabolic rate. The computer program TEMPAL is used to predict internal environmental conditions within a dwelling. TEMPAL is shown to be sufficiently accurate for this purpose by comparing predictions with monitored conditions.

The air velocities and air temperatures distributions within the occupied zone of a room were determined and the wall surface temperatures were measured, in steady-state conditions. For each one of the 5 selected comfort criteria, and at every point of a three-dimensional network, a comfort index, derived from the physical measurements, characterizes the level of discomfort. The data is then synthesized in the form of a comfort profile, taking into account not only the frequency of the 5 types of discomfort, but their intensity as well.

Air flow in an enclosed space, whether from natural or mechanical ventilation, has generally a rather slow velocity, 0.1-0.25 m/s, but may still cause local discomfort. Tests were carried out on laminar and turbulent air flows in this velocity range. Turbulent air flow was found to always cause more discomfort than linear air flow.

A test chamber was designed and constructed at Princeton University for research purposes. The structure is essentially a miniature house, with no internal partitions, built with simplicity and uniformity in mind. Also thetest chamber was built to have minimal infiltration rates, and with versatility to facilitate experimentation. The test chamber is a tool to study subtle effects in the thermal performance of structures.

A survey was carried out on 15 homes in Northern Italy to evaluate the occurrence of 35 selected volatile organic compounds and of total volatile organics in indoor air and in ambient (outdoor) air. Respirable suspended particulates and venti

A representative panel of 37 conventional houses in Eastern Pennsylvania was chosen. Each house was located with respect to its geological formation (the underlying substrate). Blower-door ventilation measurements were made. The concentration of radon in the domestic water supplies was analysed and passive radon monitors were used to measure the radon in the air. It was concluded that the radon in these houses arises largely from the soil and passes through the foundations.

Regulations relating to building design, construction and occupancy in the various States of the USA are examined to assess the technical bases for their ventilation provisions and to determine if they permit innovation in indoor air quality technology.