Need clarification regarding patient room branch circuits

[riverjig87]

This is in reference to Article 517.19 (C) " Patient Vicinity Grounding and Bonding - Optional"......FPN

In the code, it is permitted to have patient equipment grounding point. The installation of said EG is permitted to be centrically or looped as convenient.
Now, in the the fine print note, it states that you are to keep the distace between the reference grounding point and patient vicinity as short as possible.
We would like to loop this EG between about 10 patient rooms. It doesnt give a specific length or distance. How are we to interpret this?

I have looked in the 2005 handbook and all examples show only one patient room. I would love to know the exact meaning of this.Thanks for any help.

 

[roger]

The FPN actually says "Where there is no patient equipment grounding point, it is important that the distance between the reference grounding point and the patient vicinity be as short as possible to minimize any potential differences."

The "reference grounding point" is the grounding bus in the panels (both Critical and Normal) serving the room.


Reference Grounding Point. The ground bus of the panelboard or isolated power system panel supplying the patient care area.


After your installation all grounds will have to meet the less than .01 ohm criteria (with a bio med analyzer) per NFPA 99 chapter 4 and the longer the length the harder this will be to achieve.

Roger

 

[riverjig87]

awesome. thank you for the help. Its a great answer.