Dental Practice

[JC94]

Got a call about installing socket outlets in a small very basic dental practice (1 Floor, 2 Surgery rooms containing a dentist chair in each, presumably one or both have small x-ray machines and that's about it from when I went to check it out. And then a reception area and waiting room). They wanted the outlets for computers to be plugged in, approx 4 computers.

I was thinking about running a dedicated clean RFC for the computer outlets only as access wasn't an issue, but they have an old SP 3036 board so I spoke to them about a board change before any new socket outlets go in.

Checked medical locations in BYB but nothing about dentists - any pointers as to where i'd find them, in regards to certain equipment that shouldn't be RCD protected etc. Some of the outlets are at access to the public (in the reception area to charge phones etc while they wait) so opted for RCD protection as they fall under "Ordinary Person".

Current board is not labelled so will be tracing circuits Monday before board change over, from the initial survey the chairs were on 13a FCUs presumably on the existing ring final

 

[Leesparkykent]

Is a dentist not a medical location then?

 

[JC94]

Is a dentist not a medical location then?

I have always took it as that yes, but had a moment of doubt.

 

[Leesparkykent]

I have always took it as that yes, but had a moment of doubt.

Medical Locations are allocated a grouping signifier, as follows:
group 0
Medical location where no applied parts are intended to be used and where discontinuity (failure) of the supply cannot cause danger to life.
Examples of group 0 include consultant examination rooms or massage rooms.

group 1
Medical location where discontinuity of the electrical supply does not represent a threat to the safety of the patient and applied parts are intended to be used externally or invasively to any part of the body except where group 2 applies.

group 2
Medical location where applied parts are intended to be used, where discontinuity (failure) of the supply can cause danger to life, in applications such as intracardiac procedures or vital treatments and operations.

 

[JC94]

Medical Locations are allocated a grouping signifier, as follows:
group 0
Medical location where no applied parts are intended to be used and where discontinuity (failure) of the supply cannot cause danger to life.
Examples of group 0 include consultant examination rooms or massage rooms.

group 1
Medical location where discontinuity of the electrical supply does not represent a threat to the safety of the patient and applied parts are intended to be used externally or invasively to any part of the body except where group 2 applies.

group 2
Medical location where applied parts are intended to be used, where discontinuity (failure) of the supply can cause danger to life, in applications such as intracardiac procedures or vital treatments and operations.

Cheers, that's what I was after, i've only done one dental practice before under my old boss and the chairs had dedicated circuits. With it not being marked up i'm going worst case scenario they are on the existing socket outlet circuit until I can check them on monday. If they are that then brings up the point of they'll be on the RCD or putting them on their own dedicated.

 

[Leesparkykent]

Cheers, that's what I was after, i've only done one dental practice before under my old boss and the chairs had dedicated circuits. With it not being marked up i'm going worst case scenario they are on the existing socket outlet circuit until I can check them on monday. If they are that then brings up the point of they'll be on the RCD or putting them on their own dedicated.

As medical locations of groups 1 and 2 have more onerous practices occurring within when compared to group 0, a 25 V a.c. or 60 V d.c. limit is imposed between exposed conductive and/or extraneous conductive-parts under fault conditions. Group 0 is a location where applied parts are not intended to be used and is less onerous, in terms of risk of electric shock, when compared to groups 1 and 2, therefore, the common rules of BS 7671 apply in group 0.

 

[JC94]

As medical locations of groups 1 and 2 have more onerous practices occurring within when compared to group 0, a 25 V a.c. or 60 V d.c. limit is imposed between exposed conductive and/or extraneous conductive-parts under fault conditions. Group 0 is a location where applied parts are not intended to be used and is less onerous, in terms of risk of electric shock, when compared to groups 1 and 2, therefore, the common rules of BS 7671 apply in group 0.

With a dental operating room being in group 1, the chair has a transformer inside thus making it PELV? I understand the supply to the chair but the chair itself not as much

Thanks for your replies also

 

[Leesparkykent]

Guide to Electrical Installations in Medical Locations - IET Electrical

Guidance Note 7: Special Location, 4th Edition - IET Electrical

These would make a good read.

 

[ipf]

Ah!!!!!! But is it safe?
https://www.youtube.com/watch?v=kzw1_2b-I7A

 

[Paul.M]

The sockets in the communal/public areas change them for RCD sockets, no need for a board change. As for the sockets in the medical area, you can buy bacteria resistant sockets. They have silver (and over materials in them) that means the sockets reduce the build up of bacteria from dust etc. From memory they cost about £20 each but it may be a spec for your type of install, check that out before you start.


ps, great advice from Lee yet again.

 

[Farmelectrics]

make sure you over charge them put an extra £50 on ive just been ripped off swollen mouth and £51 for a tooth out ha ha robbers