Introduction

By using this document, you can construct subjective scales that can be used to ask people how they feel about their physical environment. That is whether they find it too hot, whether there is any noise and if it is annoying, if the light is too bright, is it “smelly” and so on. By constructing the scales and using them correctly, you can see, in a cost-effective way, how people find the environment. The information can be applied to report on the environmental quality and to work out how to improve the environment.

People are exposed to a range of physical environments which can affect their health and safety, comfort and performance. An important method for assessing physical environments, particularly when considering psychological constructs such as comfort or satisfaction, is to use subjective scales. The type of scale used and how it is administered is important in influencing the subjective responses of people. There are principles for constructing scales and procedures for administering them that reduce bias and ensure validity and reliability of response. There are also generic types of scale that can be used across environmental stimuli, for example, scales on which people rate sensation or comfort or acceptability or preference and so on.

This document provides a description of principles of scale construction and procedures for use. It also provides examples of commonly used scales across environmental components. This document does not standardize any particular scale but it provides the principles upon which appropriate scales can be constructed. It is needed to provide consistency in the production of valid and reliable scales. It is particularly useful to people who wish to conduct an environmental survey, for example to assess post occupant satisfaction of new or existing buildings or other spaces, environments where dissatisfaction occurs and a diagnosis of the problems is required and for people who are investigating the relationship between conditions in the physical environment and human perception. A consistent approach to subjective scale construction and use also allows a meaningful comparison of data obtained from investigations internationally.

This document forms part of a group of international standards on the assessment of comfort, stress and strain in physical environments.

This series is concerned, in particular, with:

1) establishing specifications on methods for measuring and estimating the characteristic physical parameters of environments;
2) establishing methods for assessing stress in environments.

This document proposes a set of specifications on direct expert assessment of comfort/discomfort expressed by persons subjected to various degrees of stress during periods spent in physical environments. The data provided by this assessment can be used on its own or to supplement physical and physiological methods of assessing loads. The methods belong to a psychological approach consisting in gathering, as appropriate, the on-site opinions of persons exposed to the conditions under consideration (diagnosis) and, thus, can complement data provided by predictive approaches described elsewhere in this group. The information provided in this document can be used to construct valid subjective scales for use in determining how people feel in their physical environment. This document does not give guidance on questionnaire design and application although the scales may be used in the construction of questionnaires.

If persons exposed to environments are to be asked about their corresponding experiences or information requested on their cultural attitude in order to obtain the most appropriate subjective judgement scales, favourable relationships may usefully be established between these persons and the organization responsible, through the persons conducting the ergonomic investigation.

The environments which lend themselves to the application of subjective judgement scales relate to conditions which differ to a moderate degree from comfortable conditions. Under extreme conditions, physical and physiological assessment methods of the environmental load are preferred, provided that their results can be used as criteria for a decision. In particular, tolerance limits for load cannot be confidently based on subjective judgements and need to be decided in view of accepted health risk criteria. The decision of whether a person is exposed to an extreme environment is not left to the person exposed as their judgement can be impaired by the conditions.

The opinions held by persons about their environment have a value in themselves. It is up to the ergonomist whether or not to take them into account. The reputation of these data for lack of reliability does not justify dismissing them out of hand. The aim of this document is precisely to improve their reliability by specifying the appropriate tools to use in collecting them and the requirement for using them.

BS EN ISO 10551:2019

Ergonomics of the physical environment. Subjective judgement scales for assessing physical environments

Current

Published:

31 Aug 2019