ANSI/IES LS-1-22, Lighting Science: Nomenclature and Definitions for Illuminating Engineering
The IES defines illumination engineering terms in ANSI/IES LS-1-22, is available here online. You can search terms by their first letter using the categories listed in the Categories window, by the first letter of the term in the alphabetical list below, or by typing the term in the search window. You can find the Introduction material for LS-1-22 on these pages:
- Copyright, Disclaimer, and American National Standards Statement
- Foreword, Nomenclature Committee members, Introduction, and Scope
- Spectral Parameters Used in Illumination Engineering
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- U.S. Customary System (USCS, formerly English) unit of luminance
- ultraviolet germicidal irradiation (UVGI)
- ultraviolet germicidal lamp
- ultraviolet hazard function
- ultraviolet lamp
- ultraviolet radiation
- ultraviolet subdivisions
- unified glare rating, UGR
- uniform chromaticity scale diagram (UCS)
- unilateral sidelighting
- unit (lighting equipment)
- units of luminous exitance
- units of wavelength
- univariance
- unrecoverable light loss factor
- upper (driving) beams
- upward component