Research into air flows, heating systems and ventilation

Use of computers for simulation of air flows in buildings, leading to production of a mathematical model for analysing the stability of ventilation systems subjected to external forces, and for simulation of heating systems toproduce a mathematical model of heat release and water flow in radiator systems. Investigation of fire ventilation.

Application of the constant concentration technique for ventilation measurement to large buildings.

The British Gas 'Autovent' system utilises the constant concentration technique and was developed for measuring ventilation rates in dwellings. It has recently been used in two large open-plan buildings, a school nursery and a factory unit, and the opportunity was taken to carry out special tests to assess its validity in such buildings. The reason why these tests were needed, the nature of the tests and the results obtained form the main content of the paper. The evidence from the tests strongly indicates that the system is suitable.

Stability of body odour in enclosed spaces

Sedentary subjects occupied an environmental chamber (20-22 deg C, 35-50% RH) with low ventilation for 90 min. Judges (visitors) evaluated the odour of the chamber before and during, and after the 90-min period of occupancy. Odour intensity increased throughout occupancy and decayed afterwards. However, therate of decay exceeded that anticipated from ventilation rate alone. The results implied that body odour is unstable with a half-life of 55 min. This instability will influence quantitative requirements for ventilation during nonsmoking occupancy.

Case study of a sick building

Demonstrates that complaints by office staff about their physical environment are not necessarily caused by physical deficiencies. Trying to reduce the level of complaints by adjusting heating ventilating and air conditioning (HVAC) systems can therefore be an unrewarding task. Greater attention needs to be placed on - communications between management, those responsible for running HVAC systems and staff. Staff need the feeling that they can influence, if not control, their environment. Staff should also have more realistic expectations about their thermal comfort.

Indoor climate problems in a kindergarten, and how they were solved

An account is given of what the kindergarten staff wrongly believed caused the problems and what measures they carried out in an attempt to solve them. On the spot measurements showed however what the real main cause of the problems was. Results from the comprehensive measurements of CO2 concentrations andother ventilation performance criteria in a room occupied by 12 children and 3adults are then presented.

Sick building syndrome

Random samples of the workforces of an air conditioned and naturally ventilated building were interviewed using a doctor administered questionnaire. Large and statistically significant excesses of work-related nasal symptoms, irritation of the eyes, dry throat, headache, dry skin andlethargy were detected in the air conditioned building compared to the naturally ventilated building. In the air conditioned building, over 36% of those interviewed were suffering from a single symptom and few workers were symptom free.

An office environment - problems and improvements

The employees in a large office in Trondheim were complaining about headache, tiredness, sickness, allergic reactions in eye and nose, dry skin, respiratory diseases etc., and as usual they believed that their inconvenience was due tothe ventilating system. However, preliminary investigations did not verify this assumption, although it was evident that the heating and ventilating system was part of the problems. Measures included reduction of room temperature, antistatic treatment of carpets, and replacement of noisy ceiling diffusers.

HVAC system operational parameters affect airborne fungal levels in occupied spaces

The National Institute for Occupational Safety and Health (NIOSH) and the U.S. Army, Construction Engineering Research Laboratory (USA-CERL) have collaborated on a project that examines the influence of heating, ventilation, and air-conditioning (HVAC) system operational parameters on the levels of microorganisms found in a simulated office space. In these experiments, fungi were collected as representative microorganisms using side-by-side sieve and slit samplers. Experiments at USA-CERL demonstrated that fan coil units are a major source of fungal aerosols in the built environment.

Factors influencing formaldehyde levels in manufactured housing

A matched pair of identical mobile homes, one supplied with electric heating and cooking utilities and the other with propane gas utilities, were used to evaluate, over a 14-month period, various factors which may affect indoor formaldehyde c

Mobile laboratory for sensory air quality studies in non-industrial environments

A mobile laboratory has been constructed for the sensory analysis of air quality in the field. It is used as a human exposure chamber for prolonged exposure to low concentration pollutants, a generator chamber for air pollutants, and a pollut

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