UL has published Design Guide 24480, Design Guideline for Promoting Circadian Entrainment with Light for Day-Active People. The goal of the 60-page guide is to encourage lighting practitioners to provide daytime light levels in buildings that promote a more natural pattern of bright days and dim nights, which is conducive to circadian health.
While not an ANSI document, the writing committee included a cross-section of the industry and underwent two public reviews in 2019. The Illuminating Engineering Society is reportedly working on an ANSI recommended practice, though it’s uncertain when it will be published.
This guide makes circadian-supportive lighting strategies more actionable. To check it out, click here and type in a search for “24480.” The guide costs $402, though a digital edition is available for free viewing with an account.
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