I'm working on a LEED-CI offices project. I'd like to apply additonnal interior lighting power as specified in ASHRAE 90.1-2004 section 9.6.2b: Lighting to be installed to meet the requirements of visual display terminals. So I assumed that a computer is a visual display and the user needs more lighting for his work. So we are using a T8 luminaires under desk shelf.
To have additional power accepted, the luminaire must meet specific requierements. ASHRAE specify a maximum luminance of 80cd/ft² at 65 degrees. What the ft² refer to? Area of the desk, the floor, the luminaire? It is unclear...
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
December 17, 2012 - 2:52 pm
Is your project under LEED ID+C 2009? If so the 2004 version of 90.1 does not apply. The additional lighting you mentioned is not available in the 2007 version of the standard.
MATHIEU HOULE
AUBINPELISSIERDecember 17, 2012 - 2:57 pm
My project is in Canada. LEED Canada is a little behind and still refer to ASHRAE 2004, so additional lighting may apply. Do you know this version and what they mean about this luminance?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5909 thumbs up
December 17, 2012 - 3:40 pm
This requirement is related to glare in the vertical plane. So the square footage is in the vertical plane below the fixture.