抄録
A dimmable task lighting system was installed at six working places in a luminaire factory in France. The factory hall had skylights that prvided a lot of daylight. The purpose was to study which illuminances users select, how often they use additional task lighting, whether they liked the lighting system and if their selections were influenced by the amount of daylight or the type of work. The workers were free to use the task lighting in any way they wanted. The settings of the task lighting were recorded between the winter of 2004 and the spring of 2005. The opinions of the users were sought by means of questionnaires after the testing period. It was found that those workers who worked in the area on more than 20 days in the testing period used the task lighting (viz. switched it on) on average only during 6.5% of the total working time. The task lighting was used more frequently during the times when the amount of daylight was limited (darkness or dark weather) and less frequently when there was more daylight in the area. And the task itself also had an influence on the preferred illuminance, and hence on the frequency of use of the task lighting. The preferred horizontal task illuminances supplied by the task-lighting luminaires varied from person to person, with an average of around 600 lux. The users expressed the wish that they wanted to keep the system after the test period, and 41 per cent of the users felt that the task lighting helped them to perform better.
