Critical lighting only in a x-ray room in a hospital

[Cartoon1]

Hi all. I'm putting some lights for an x-ray room in a hospital where someone lays on a bed and they take some x-rays (there will be no surgical operations or anything anesthesia). Total 6 lights fixtures, i put 4 on critical branch and 2 on normal power. My question is can all the lights be on the critical circuit? Is normal required?

I'm trying to go per 517.18(A) and 517.19 but I'm not sure if that covers lights in this scenario?

Thank you

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[garbo]

I worked ten years at a large hospital and they had numerous own way of doing things but always equal or above the NEC requirements. One being all 24 elevators were on emergency power. Think code only requires 50% of the elevators to be supplied by emergency power. I would check with the AHJ on this. While performing yearly & tri annual maintenance or replacing ATS'S on Sunday mornings we had to secure various circuits on emergency backed up power. We had to move plugs on red emergency receptacles to normal power receptacles. To me it would be more practical to have luminares split up. Some on normal power and the remainder on emergency power. Guess that I did not a top secret security hospital clearance for a detailed list that told you what circuits had to be on critical power, life safety etc that I asked for several times.

 

[roger]

Have you looked into NFPA 99 requirements. As far as the NEC 517.33 requires Critical Branch lighting but nothing actually requires normal branch lighting however I would want at least two circuits regardless for good design.

 

[Cartoon1]

Have you looked into NFPA 99 requirements. As far as the NEC 517.33 requires Critical Branch lighting but nothing actually requires normal branch lighting however I would want at least two circuits regardless for good design.

Agreed there with the good design statement. In this case this question came up from the contractor and i couldn't really say no because i didn't see anywhere in the code that didn't allow it.

I worked ten years at a large hospital and they had numerous own way of doing things but always equal or above the NEC requirements. One being all 24 elevators were on emergency power. Think code only requires 50% of the elevators to be supplied by emergency power. I would check with the AHJ on this. While performing yearly & tri annual maintenance or replacing ATS'S on Sunday mornings we had to secure various circuits on emergency backed up power. We had to move plugs on red emergency receptacles to normal power receptacles. To me it would be more practical to have luminares split up. Some on normal power and the remainder on emergency power. Guess that I did not a top secret security hospital clearance for a detailed list that told you what circuits had to be on critical power, life safety etc that I asked for several times.

yes agreed, sometimes it is a mess to figure out what everyone wants in those type facilities.

 

[garbo]

Have you looked into NFPA 99 requirements. As far as the NEC 517.33 requires Critical Branch lighting but nothing actually requires normal branch lighting however I would want at least two circuits regardless for good design.

While talking g about good design when they built a $700 million 12 floor ambutory care building they had over 70 12 by 12 or 14' exam rooms on one floor with 1 luminare on normal power and other on emergency power. The 225 amp emergency 480/277 lightning panel had 42 bolt on 20 amp circuit breakers installed but only 3 or 4 breakers were used. Of course they only feed the 70 plus rooms with only two breakers and when they had to replace a ballast in a hi hat they had to come in early to Lotto the 277 volt and ended up getting two hours overtime. For some reason they ran the 277 volt feed to hi hat j box then to switch.