IECC 2009 and the Massachusetts Energy code

[mshields]

We are doing an Ambulatory Surgical Center and I'm currently working on the lighting calcs to make sure I meet the Mass Building Code which is essentially the IECC 2009.

My question has to do with the OR's. In the OR's we've downlights around the ourside perimeter of the room and then in a square around the OR Table made up of 2x4's each with 6 lamps 32Watt T8 lamps. And in the center of these is, of course, the exam light.

Obiously I don't have to include the Exam light but what about these 2 x 4 fixtures in the center. To me, these are tasks lights. They wouldn't be so intense were it not for the process going on underneath them and the energy code ought not to drive how bright we can make these.

A colleague of mine insist that these fall into the "general lighting" category and that therefore we must include them in our calc toward the required watts per square foot (1.2).

What do you think?

Thanks,

Mike

 

[chris kennedy]

Hello Mike, welcome. This may help.

505.5.1 Total connected interior lighting power. The total connected interior lighting power (watts) shall be the sum of the watts of all interior lighting equipment as determined in accordance with Sections 505.5.1.1 through 505.5.1.4. Exceptions:

1. The connected power associated with the following lighting equipment is not included in calculating total connected lighting power.

1.1. Professional sports arena playing field lighting.

1.2. Sleeping unit lighting in hotels, motels, boarding houses or similar buildings.

1.3. Emergency lighting automatically off during normal building operation.

1.4. Lighting in spaces specifically designed for use by occupants with special lighting needs including the visually impaired visual impairment and other medical and age-related issues.

1.5. Lighting in interior spaces that have been specifically designated as a registered interior historic landmark.

2. Lighting equipment used for the following shall be exempt provided that it is in addition to general lighting and is controlled by an independent control device:

2.1. Task lighting for medical and dental purposes.

 

[mshields]

Hey Chris - Great to see you manning this post as well.

I had reviewed all that and to me, there is a certain degree of subjectivity as to what you call task lighting. The light level provided by this intense grouping of fluorescent fixtures is, after all, designed to provide 100 fc's or so, specifically for the task at hand. i.e. to conduct an operation. I can't imagine that it is the intent of the energy code to any way drive or limit the output of these fixtures.

 

[TJacobs]

You will probably need to justify those fixtures as task lights to the AHJ.

 

[Paul Sweet]

Just ask him if he would want to undergo an operation without them.