Circadian light doses received during typical daily activities
We now know more about the photoreceptor system which controls our circadian cycle. It explains how light is affecting our health and well being. There is also some agreement on the spectral response curve of this system and we know that the light dose coming to our eyes is what matters. This study investigates how much light our eyes receive throughout our daily activities. We defined seven profiles typical of a an office worker, a night shift nurse, a sportsman...Living the day of each profile, we measured every 2 minutes, the spectrum of light coming into the plane of our eye. This was done in May 2006, in Lyon, France. We computed a circadian illuminance by combining spectral irradiances with the spectral response curve proposed by Thapan (Thapan, 2001). The arcadian illuminances were then integrated over time to produce circadian light doses, for each activity and for the whole day.The results show that the night shift nurse receives the lowest daily light dose: 4265 circadian lux.h while the sportsman receives the highest: 128520 circadian lux.h. The activities through which we are exposing ourselves to daylight: waiting for the bus, walking to a cafeteria for lunch, jogging...provide circadian light doses which far exceed those provided by indoor activities. Daylight has the right spectrum for our health. This is not so surprising since we have evolved under daylight. Public health recommendations should include daily exposure to outdoor daylight.
circadian system light dose health daylight spectral irradiances.
Dumortier Dominique Nollet Hugues Cooper Howard Gronfier Claude
DGCB-LASH INSERM, Lyon, France
国际会议
26th Session of the CIE(国际照明委员会（CIE）第26届大会)
北京
英文
1076-1079
2007-07-04（万方平台首次上网日期，不代表论文的发表时间）