A Voltimum user was working on the wiring at a therapy centre but was unsure if the dialysis machines needed to be protected by RCDs.
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Question:
I have to do the wiring for a dialysis therapy centre. I was told that the sockets for the Dialysis machines/chairs should not be on RCBOs ( RCD Device). The reasons given are (1) to avoid the risk of danger that would be created through nuisance or unwanted tripping of the RCD device during patient treatment, thereby causing harm to the patient and (2) having the RCBO would make the circuit more prone to going off and disturbing the patient treatment, thereby causing harm to the patient.
I need guidance on this as I have already purchased 11- B16 RCBOs (30 mA, AC type), one for each Dialysis Machine.
1) Should I replace the RCBOs with CBs and why or why not?
2) If RCBOs is to be used, what type (AC or A) and what trip current ( 30 mA, or 100 mA) should I use?
Answer:
Richard Atkins, NICEIC, Technical Standards Engineer
Regulation 411.3.3 for additional protection for socket outlets with a rating not exceeding 20 amps allows two exceptions where the RCD can be omitted.
Exception (a) states: ‘where other than for a dwelling, a documented risk assessment determines that the RCD protection is not necessary.’
Omitting the RCD on the basis of a risk assessment is a serious matter and should be carried out in accordance with The Management of Health and Safety Regulations 1999.
A copy of the risk assessment must be attached to the Electrical Installation Certificate or where applicable the Minor Work Certificate.