standard

The revision of Ashrae standard 62, Ventilation for Acceptable Indoor Air Quality, began in 1991. This article gives a summary of the changes that have been approved and describes the issues that remain to be resolved.

Describes the content of the European and International standard EN-ISO 13792 which allows the simplified calculation of the internal temperature in hot season of a room without mechanical cooling.

The article presents the scope and content of ISO 13790 standard which is intended to calculate the energy use for space heating of buildings. Information is given about the accuracy of the standard calculation method.

Describes the thermal model available, both simple and complex and outlines capabilities and limitations. States that all of the models have limitations for use in standards, including the accuracy of the physical simulation and the accuracy of the inputs to the model. States that the biggest limitation is probably the accuracy with which comfort perceptions can be related to the physiological variables simulated in the thermal models.

Describes the current design standard BS EN ISO7730 - 'Moderate thermal environments - determination of the PMV and PPD indices and specification of the conditions for thermal comfort'. States that it is based on Fanger's work and comprises a steady-state human heat balance model that leads to a prediction of the sensation of human thermal comfort for a given set of thermal conditions. Questions the applicability of this standard when confronted with the more complex environment of a chilled ceiling operated in combination with displacement ventilation.

Explains the origin and development of the adaptive approach to thermal comfort. Considers several recent developments in the application of the theory and the origin of the differences between adaptive thermal comfort and the 'rational' indices. Explores its application to comfort standards and makes recommendations about the best comfort temperature, the range of comfortable environments and the maximum rate of change of indoor temperature. Also mentions the application of criteria of sustainability to thermal standards for buildings.

A new adaptive comfort standard is included in recently accepted revisions to ASHRAE Standard 55 - 'thermal environmental conditions for human occupancy'. The new standard allows warmer indoor temperatures for naturally ventilated buildings during summer and in warmer climate zones. The paper summarises the research carried out to formulate this new standard, presents some of the findings for naturally ventilated buildings, and discusses the standardization process. Suggests ways to use the ACS for the design, operation and evaluation of buildings and for research.

Describes existing ISO standards and current projects concerning thermal comfort. Describes the production process for ISO standards. Considers the existing EN ISO 7730 thermal comfort standard in these terms and also ISO 8996 (metabolic rate0 and ISO 9920 (clothing). Also presents the work of ISO/TC 159 SC5, 'ergonomics of the physical environment'. Gives a detailed presentation of the proposed revision of EN ISO 7730. This will be based on requirements for general thermal comfort, operative temperature and local thermal discomfort.

Brief article introducing issues in the topic of thermal comfort standards and outlining papers from a recent conference on the subject held at Windsor, UK.

Reviews several key aspects of ventilation and indoor air quality standards. Also highlights the complexity of the IAQ issues from the standardization viewpoint. Detailed technical solutions are dependent on project-specific criteria including climatic, cultural and other aspects as well as differences in national regulations, standards, guidelines and available IAQ technologies.