Dental Surgery rooms-Isolated grounds-Emergency power

[Ithinkimstillhere]

I have a project for an existing building. It used to be a dental clinic (B occupancy), then something else, now its switching back to a dental clinic as a full renovation (7 operatories and 3 surgery rooms). The current building doesn't not have generator back up, but our client wants it. He wants all three surgery rooms (I.V anesthesia will be giving in these location) on e-power and the rooms associated HVAC.

As I will have two transfer switches, one for life safety (egress lighting and fire alarm) and one for critical power (for the surgery rooms), Do I need an isolation transformer and panel fed from the critical branch exclusive for the surgery room, or can I just feed the room from the critical panel?

 

[roger]

Check your state rules. Isolated Power Systems are not required by NFPA 70 nor NFPA 99, they are options. Some states have left them behind for GFCI's

Roger

 

[david]

I have a project for an existing building. It used to be a dental clinic (B occupancy), then something else, now its switching back to a dental clinic as a full renovation (7 operatories and 3 surgery rooms). The current building doesn't not have generator back up, but our client wants it. He wants all three surgery rooms (I.V anesthesia will be giving in these location) on e-power and the rooms associated HVAC.

As I will have two transfer switches, one for life safety (egress lighting and fire alarm) and one for critical power (for the surgery rooms), Do I need an isolation transformer and panel fed from the critical branch exclusive for the surgery room, or can I just feed the room from the critical panel?

I would think the rooms would also need normal power

Just curious where are you feeding the HVAC equipment from

 

[Ithinkimstillhere]

I would think the rooms would also need normal power

Just curious where are you feeding the HVAC equipment from

The HVAC equipment associated with these rooms will be fed from the same critical branch panel as the room receptacles and lights (all 120/208V)........generator>transfer switch>branch panel>HVAC, lighting, receptacles

 

[Dennis Alwon]

I believe those treatment rooms need to be wired with mc but I am not certain that an isolated ground is need.

 

[roger]

I know the OP used the term Isolated ground in the title but, since Isolated grounds are prohibited in Patient Care Areas I assumed he was talking about Isolated Power Systems.

Here are some pertinent article sections for the OR's, 517.13, 517.14, 517.16, (prohibits Isolated Grounds) 517.19, (read all of it) 517.30(C)(3), and 517.160

Roger