English

It is not unusual to face moisture problems in buildings in cold climates and wet regions. It is, however, unusual to have the same problem in a relatively dry region such as Jordon, which has moderate weather conditions and mild winters. Nevertheless, a significant proportion of houses and residential apartments in Jordan are affected. The monitoring of inside air conditions, wall surface temperatures, ventilation and living style has shown that a high relative humidity (RH >75%) occurs at walls resulting in possible condensation.

Air supply volumes and velocities in cleanrooms are monitored by airflow measuring hoods and anemometers but these measuring methods can be inaccurate if used incorrectly. It is demonstrated in this article that measuring hoods are accurate if the air supply passes evenly out of the hood, as occurs when the air volume is measured from a four-way diffuser or no air supply diffuser. However, when a swirl diffuser was investigated, the measuring hood gave readings more than 50% greater than the true volume. The reasons for the inaccuracy, and methods to correct it were established.

Air curtains are used to eliminate airflows through doorways (doorway tightness). In this paper the impacts of air circulation, jet discharge momentum flux and nozzle design parameters on the tightness of an upwards blowing air curtain are presented. The tightness values were measured using a tracer gas decay method in the laboratory hall. Measurements were undertaken for two nozzle widths, 30 mm and 120 mm, and for two different discharge angles, 10° and 30°.

An experimental study of annular jets with central aspiration is presented. Two flow regimes were studied for creating either local air conditioning or local ventilation systems. The local air-conditioning system was developed by maintaining the same flow rates of the non-swirling annular jet and central aspiration. A new concept of a 'local ventilation system' was created by combining the swirling annular air jet impinging on the plate and central aspiration.

The impact of ventilation on indoor particulate pollution is highlighted by numerous studies. The aim of the present study is to examine the influence of ventilation on the levels of particulate concentrations found in dining halls where a large number of students are accommodated. Indoor particulate sources were also quantified and their influence on the particulate concentrations was examined.

Computational Fluid Dynamics (CFD) is evidently relevant to the study of fires, yet the intermediate chemistry has yet to be factored successfully into combustion models. Consequently, predicted airflow patterns, together with pressure and temperature contours, are mostly used in evaluating the performance of smoke control systems. But even using these assumptions, very few studies exist comparing predicted results from CFD with experimental findings. This leaves research with a paucity of data on how smoke is likely to spread, fill and be controlled in large halls.

Emergency smoke ventilation for a uni-directional traffic road tunnel is studied using a CFD modelling approach. Fire scenarios in an uphill ramp for congested traffic conditions have been considered. Based on a longitudinal smoke ventilation system with a damper smoke-extraction device on the ceiling soffit, the impact of longitudinal ventilation (LV) control, operation of fire suppression intervention and emergency response delay have been quantitatively investigated.

CFD modelling techniques have been used to simulate the coupled external and internal flow in a cubic building with two dominant openings. CFD predictions of the time-averaged cross ventilation flow rates have been validated against full-scale experimental data under various weather conditions in England. RANS model predictions proved reliable when wind directions were near normal to the vent openings. However, when the fluctuating ventilation rate exceeded the mean flow, RANS models were incapable of predicting the total ventilation rate.

Considering the likelihood of contributions of various indoor air pollutants to detrimental health effects, the Community-COST Concertation Committee of the Concerted Action "Indoor Air Quality and its lmpact on Man" (COST Project 61 3) decided that indoor radon is a well studied indoor pollutant both in terms of occurring concentrations and expected adverse health effects. In July 1985 the Article 31 Euratom Treaty Group of Experts set up a Working Party to study and report on this matter.

The UK construction industry is beginning to take notice of Post Occupancy Evaluations (POE) of completed buildings. POE studies have found that actual energy consumption in buildings often bears no resemblance to design predictions and low-level comfort problems persist. In the UK, there are a growing number of supporters for the routine use of POE in the construction industry. This paper discusses the in-use performance of an Advanced Naturally Ventilated secondary school building in the UK.