TY - JOUR
AU - Hull, C.J.
AB -  I refer to Dr Hull's reply to my letter in your columns (Anaesthesia 1979; 3 :9154). I had thought it unne4 cessary to mention that the enclosures (metal cases) of all electro-medical equipment, whether supplied by earth-free mains or not, are earthed. What I wished to emphasise was that in spite of the installation of an isolating transformer supplying a group of rooms, or even a single operating theatre, there was no guarantee that the power supply was in fact earth-free. Not only may there arise a fault in which a direct contact is made between a power circuit and the enclosure, another metal part of the equipment or permanent wiring installation, but also there are leakage currents arising within both the equipment and the fixed wiring of a sufficient magnitude to predispose to micro-shock or even gross electrocution via earth. Thus the very expensive exercise of installing isolating transformers to theatres or departments cannot be relied upon to ensure safe conditions and we should view such a policy with caution. The present means of earthing all equipment and isolating all patient circuits is far more reliable. I trust that nobody will read into the above remarks that 
TI - On electrical safety
JF - Anaesthesia
DO - 10.1111/j.1365-2044.1980.tb03959.x
DA - 1980-09-01
UR - https://www.deepdyve.com/lp/wiley/on-electrical-safety-WM036LdIZf
SP - 921
VL - 35
IS - 9
DP - DeepDyve
ER -