Investigates the ventilation efficiency of different ventilation patterns arranged by two inlet and two outlet diffusers at different locations. First performs a numerical simulation, then a laboratory test in a full scale test chamber to validate the results. A concentration decay of carbon dioxide was used to calculate the ventilation efficiency and air change rate for the test chamber. States that the location of diffuser rather than air change rate might dominate the distribution of supply/exhaust air in the study.

States that there are problems involved with the use of traditional instruments such as vane anemometers and pitot tubes when measuring airflow rates in HVAC systems in order to balance air distribution. Suggests that the simple and useful tracer gas techniques that are commonly used for ventilation measurements in buildings can be a suitable alternative. Describes a preliminary study intended to determine the viability and accuracy of the tracer gas technique. A good correlation between the airflow rates measured by using a pitot tube and tracer technique was found.

States that to control humidity it is necessary to remove moisture load from ventilation air. The combination of increased ventilation and air conditioning brings more humidity in from outdoors with a greater chance that condensation will occur on surfaces chilled by the cooling system. Suggests that rooftop equipment for cooling is frequently oversized. Considers the nature and dimensions of the moisture loads.

Results from pre- and postconstruction radon measurements in a new housing development are presented. The houses were built in an area that had not been previously associated with elevated indoor radon concentrations. Exhalation measurements of gravel and stone from the site and soil gas measurements under several houses did not indicate an elevated radon potential. However, 4 of 21 finished houses (or 19%) exhibited annual average indoor radon concentrations over 200 Bq.m-3 (5.4 pCi/l).

The provision of underground parking facilities (UPFs) has become a necessity particularly in densely populated urban areas and business districts. Indoor air quality (IAQ) in such facilities is of great concern due to vehicle induced emissions. This paper presents and IAQ assessment at six representative UPFs in Beirut using carbon monoxide and volatile organic compounds as IAQ indicators. For this purpose, concentrations of both pollutants were measured at different time intervals throughout the day. Vehicular emission factors (EFs) were estimated using the EMFAC7F1.1 model.

Designing a ventilation system for a laboratory is challenging not only because these facilities consume a lot of energy and may contain materials that are toxic, flammable, explosive, infectious, or radioactive, but because standards and codes concerning them are revised often to reflect stricter health and safety requirements and improvements in technology.

States that to be effective, insulation must be installed correctly. Studies have shown that even small imperfections in how insulation is installed will significantly reduce its performance. There are problems associated with the settlement of loose fill insulation, and batt insulation can also sag and create voids - especially if they are not the full depth of the wall, of if they are narrower than the framing space into which they are put. Insulation installers usually work on a piecework basis, so have an incentive to cut corners.

The Eden project consists of two massive 'biomes' situated at the bottom of a former clay pit in Cornwall, UK. They mimic a 'humid-tropic' and a 'warm-temperate' environment and each houses a wealth of plant life. The aim is to let plants grow naturally in a climate designed to mirror nature as closely as possible. A Horticultural Management System monitors temperature conditions and there is a separate humidity control system. There are 24 Moducel air handling units in the humid tropics biome.

Describes a new hospital whose wards will all be naturally ventilated. It is a highly serviced facility, with services accounting for 44% of the total construction cost of the building, but naturally ventilated wherever possible. The hospital is designed as a deep plan building of 38,000 sqm and is on three floors. To maximise natural ventilation, as many rooms as possible were placed on the perimeter of the building and this includes all of the wards.

Gives brief details of the Canadian Construction Materials Centre's recent evaluation of three new ridge vent products made of either three-dimensional polymeric matting or moulded plastic.