Abstract
This thesis describes a programme of study of the comparison of predicted and measured working plane illuminance. In particular a general relationship is identified which, when applied to the results reported in this study, reduces the differences between predicted and measured illuminance. The development of lighting calculations used to predict illuminance is reviewed. This identifies the changes in the calculation methods from the generally empirical approach to those based on mathematical methods involving finite elements. The role of the computer as an aid for practical lighting design is identified and described. The information gathered from the lighting survey of 59 rooms is described together with the accuracy, methodology and measurement equipment. A large number of the surveyed rooms fail to meet the recommended working plane illuminance. Using the information from the survey a computer programme is used to predict the working plane illuminance in the rooms. The computer programme is an example of good practice for practical lighting design calculations. There is a significant difference between predicted and measured illuminance, with predicted illuminance greater in 58 of the rooms. The factors which influence this difference are discussed. The influence of the floor cavity is examined in detail and described in the ''Sports Hall Experiment". This allows a relationship between working plane illuminance and effective floor cavity reflectance to be identified. Further studies are identified which would extend the relationships described in this study.