What makes medical electrical specialist work isn't the equipment — it's AS/NZS 3000 extended by AS/NZS 3003, which sets out the patient-area rules. Get the classification wrong and the room can't be used by an insurer's standard; get the bonding wrong and the room is unsafe in a way that won't show up until something else fails. We do new-fit-out medical and dental work across Melbourne, plus compliance audits and accreditation-rectification jobs in existing practices — and the documentation always lands with the practice owner in a single PDF the auditor can read in one sitting.
Body-protected vs cardiac-protected areas
AS/NZS 3003 splits treatment spaces by what touches the patient. Body-protected (Type BF) rooms are where applied equipment makes intentional skin contact — dental surgeries, GP consult rooms with ECG, podiatry suites. Cardiac-protected (Type CF) rooms are where applied equipment can come into direct contact with the heart — cardiac catheterisation, ICU bays, electrophysiology. The wiring requirements step up: shorter RCD trip times, tighter insulation-resistance tolerances, and (for CF rooms) isolated power systems instead of grounded mains. We classify each room with you during the quoting walk-through so the rough-in is correct the first time.
Equipment-specific circuits
Dental chairs, autoclaves, X-ray machines and large imaging equipment each have specific circuit requirements that don't always make it from the equipment supplier's spec sheet onto the electrician's drawings. We work directly off the manufacturer's installation manual for each item — dedicated radial circuits for autoclaves and steam sterilisers, surge protection for digital X-ray sensors, separate cleaning circuits for chair-side power so a single GFI trip doesn't take out a whole surgery. Where the equipment supplier hasn't been engaged yet, we'll quote the wiring against typical manufacturer specs and confirm against the actual spec before fit-off.
Backup power for fridges and critical loads
The most common backup-power request is a UPS for the medication fridge and the comms cabinet — typical sizing is 1–2 kVA for a small practice, runtime sized for the longest plausible outage. Larger sites with day-procedure surgical loads need a transfer switch to a generator: we install the transfer switch and the practice-side wiring (the generator unit itself comes from a specialist supplier we coordinate with). For sites without budget for a generator, a larger UPS sized to ride through a typical eastern-suburbs outage (under 90 minutes) usually covers the critical loads.
Equipotential bonding
In every body-protected or cardiac-protected room, exposed conductive parts (chair frames, equipment cabinets, gas-outlet bodies, metal trim) are bonded together to a common reference point. The bonding is what prevents a fault current from finding the patient as its lowest-impedance return path. We install the bonding bar, run the bonds (typically 4 mm² green/yellow), and provide the AS/NZS 3003 compliance test record on completion. This documentation is what the accreditation auditor checks first — we hand it over in PDF form on the same day the room is signed off.
Standards the work meets
The patient-area work is wired to AS/NZS 3003 (medical electrical installations) with AS/NZS 3000 governing everything else. Equipotential bonding, RCD trip-time testing, insulation resistance and the isolated-power system (where installed) are all commissioned and documented. A Certificate of Electrical Safety is lodged with Energy Safe Victoria for every job.