English

Explores the complexities of guidance for the ventilation of hygiene systems. The UK Health & Safety Executive estimates that 30 to 50% of refurbished buildings cause some form of sick building syndrome. It is obviously important that building managers take the necessary steps to establish programmes to maintain ductwork systems in a safe, effective and hygienic state. The UK Heating & Ventilation Contractors' Association and Building Services Research & Information Association have produced documents providing guidance on the hygienic maintenance and cleaning of ductwork.

Outlines a project to promote greater consideration of indoor air quality during building design. The project was commissioned to develop guidance on assessing the overall external pollution burden on a building and techniques for minimising indoor pollution from external sources. The guidance focuses on non-domestic buildings. It is nearing completion and is based on three main groups of pollution sources - long-range, intermediate-range and short-range.

Explains how natural ventilation can improve the environment for workers in industrial buildings as well as those in offices. States that in industrial buildings, the primary reason for installing ventilation has always been to avoid excessive internal temperatures, particularly in summer, and to provide fresh air to breath and remove odours. Waste heat from plant, processes, lighting and people is often the main problem today. Claims that natural ventilation is still an option today for cost and environmental reasons.

Maisonettes, duplexes and triplexes in the city of Montreal have enjoyed much success since they were first built some 60 to 100 years ago. They currently account for half of the city's dwelling units. However, they pose some problems in today's context. Current standards and various innovations in new housing construction serve to underscore some of the limitations. Rooms can be small, kitchen can be dysfunctional, there is little storage space. Describes research carried out to look at the potential for revitalizing plex housing.

States that condensation on windows is a major issue for building owners and managers. Tests were devised to counter the problems of sealing windows, test temperatures and cost and simulation testing for conventional testing procedures, and a database of windows that have undergone both tests and simulations for resistance to condensation was compiled. Three double hung windows of varying materials were tested as well as designs for air infiltration at several levels of airtightness.

Short analysis of possible retrofitting operations on the building envelope and on the heating system to save energy. An analysis of residential buildings in various parts of Italy has been performed using the Italian national calculation procedures (UNI) for the evaluation of winter energy need. A more detailed analysis in envisaged to extend the data obtained, using more sophisticated codes in order to calculate the annual energy consumption of the building. This would define normalised energy indices to ensure a more energy aware design.

Describes how a fully furnished two storey test house was used to perform an experimental study of tracer gas dispersion and airborne moisture movement. The test used two multizone models to simulate the experimental data. States that good agreement was obtained in the comparison and with the tracer gas dispersion. Finds that a representation of adsorption by indoor surfaces must be included in order to accurately model the airborne moisture movement.

Describes a new multicriteria analysis of ventilation during summertime in Europe. These theories are used to determine the best ventilation strategy on a university building, aiming to ensure optimum indoor air quality, occupant thermal comfort, and lower energy consumption when using accelerated diurnal or nocturnal ventilation and/or air conditioning. The article defines the possible actions, then the quality criteria for thermal comfort, indoor air quality and energy consumption.

States that it is difficult to achieve good mixing in a large space and that the usual methods to evaluate the ventilation system in such large spaces with the age of air measured by tracer gas is not often practicable. Proposes a new method to evaluate this ventilation, based on the normal step-down or decay method. A small control volume of tracer gas is used as opposed to filling the entire space. the local mean age of air is then measured in a study of the transient decay curve of the tracer gas concentration.

Explores how water gets into a structure, why it doesn't leave, and how these architectural flaws become HVAC problems. States that mechanical engineers need to understand the roots of the problems in order to defend their work if IAQ becomes a problem once the building is occupied. The article reviews air control and pressurization, ventilation and humidity control and provides some resources to help expand the reader's knowledge of design and construction errors that lead to HVAC problems.