Light Levels & Human Response

IEN had invited Dr. RatnaKala Sithravel to present her very interesting and published research on indoor light levels and its effect on the cognitive skills of humans. Interestingly, this research, which was conducted on people living in the tropics (Malaysia), reached opposite conclusions of research conducted on humans living in cooler temperate climates. Dr. RatnaKala Sithravel found that the light level in workplaces should be increased in the morning hours (9:30 - 11:30 am) to improve peoples' work performance up to 40%, namely increasing peoples' cognitive skills such as sustained attention and visual ability. The findings, which are statistically significant and published in the peer-reviewed journal Plos One, were short term exposure studies conducted on 45 persons at light levels of 250, 500, 750 and 1000 lux. For comparison, the Malaysian Standard (MS1525) recommends an office light level of 300-400 lux. IEN is in the process of writing a layman article of Dr. RatnaKala Sithravel's research findings and assisting to find additional funding for the next phase of her research.


Download the paper "Morning boost on individuals’ psychophysiological wellbeing indicators with supportive, dynamic lighting in windowlessopen-plan workplace in Malaysia" (click).


Dr. RatnaKala Sithravel, presenting 31 May 2019.


Dr. RatnaKala Sithravel, presenting to IEN Consultants on 31 May 2019.