The International Energy Agency’s (IEA) Energy Efficient End-Use Equipment (4E) Platform on Smart Sustainability in Lighting and Controls (SSLC Platform) has published a comprehensive review of the scientific knowledge acquired over the last decade on the effects of solid state lighting (SSL) on human health. This report is primarily intended to support policymakers but can also be useful to the entire lighting community.

Key Aspects of the Report

The study covers both acute and long-term effects of SSL on human health, including:

• Acute effects of optical radiation on eyes and skin
• Discomfort glare
• Circadian disruptions
• Neuro-behavioural effects
• Temporal light modulation (TLM)
• Long-term effects such as age-related macular degeneration, myopia, and cancer risk

Temporal Light Modulation (TLM)

TLM, commonly known as “flicker,” is a significant health-related topic in lighting. Dr. Jennifer Veitch, one of the report’s lead authors, notes that TLM affects human physiology and behavior with implications for health and well-being. It can cause:

• Disruption of brain activity and eye movements
• Cognitive performance degradation
• Eyestrain, headache, and fatigue
• Particularly detrimental effects on sensitive populations

Discomfort Glare

Dr. Christophe Martinsons, another lead author, highlights that some SSL products may produce high luminance levels or contrasts, causing discomfort glare. Future lighting standards should consider:

• Non-uniformity of SSL lighting sources
• Spectral distribution of the light
• Protection for sensitive groups, such as children

Overall Impact of SSL on Human Health

The report emphasizes that SSL does not have more direct negative impacts on human health than traditional light sources. However, it notes that:

• Light exposure triggers various physiological and psychological effects
• Organisms perceive electric lighting in a technology-agnostic way
• Effects occur for any light source, with varying probability and intensity

Benefits and Risks of SSL

SSL offers significant benefits, primarily in energy efficiency. However, the report identifies potential risks:

• Sensitive individuals may be unexpectedly exposed to adverse effects
• Regulations could better protect these individuals through limit values or mandatory reporting and labelling

Regulatory Considerations

The report highlights a potential conflict between energy regulations focusing on reducing light levels and the growing knowledge about daily light and dark exposure. Resolving this dilemma will require:

• Collaboration between government departments of energy, environment, and health
• Setting appropriate regulations to ensure public access to high-quality lighting
• This comprehensive review provides valuable insights for policymakers and the lighting industry, offering guidance on balancing energy efficiency with human health considerations in SSL technology.

The full report can be downloaded here.

David Shiller

David Shiller is the Publisher of LightNOW, and President of Lighting Solution Development, a North American consulting firm providing business development services to advanced lighting manufacturers. The ALA awarded David the Pillar of the Industry Award. David has co-chaired ALA’s Engineering Committee since 2010. David established MaxLite’s OEM component sales into a multi-million dollar division. He invented GU24 lamps while leading ENERGY STAR lighting programs for the US EPA. David has been published in leading lighting publications, including LD+A, enLIGHTenment Magazine, LEDs Magazine, and more.

See Full Bio