EBME Forums Forums Maintenance Technical Assistance Extension cord

Hye my friend,

In my hospital, the end user request for extension cord that used for medical equipment in Operating theatre. they want to used it because to minimize the messy condition in OT when running the operation. This is because as we well known, in one operation, at least ten equipment was used. So the messy power cord can contribute to hazard for example slipped.

I refer to my principle, they said extension cord was strictly prohibited from using in hospital but they didn't tell me why. I served in Internet I found ECRI website. It stated extension cord can be used in hospital but certain criteria need to be follow.

I quite confused, which is right? Can you all share experience in your hospital with me..

Thanks

Mains extension cables should be avoided in operating theatres (and elsewhere in the hospital, too), but ECRI is right (of course) in that sometimes they cannot be avoided.

Take a look at this solution.

Meanwhile, it might be interesting if you could share the ECRI criteria with us right here, in order to stimulate the debate, as it were.

Here's some more bed-time reading.

And (if you're really keen), here are a couple more:-

One
Two

There are a number of reasons that you need to watch out. First of all the most common fault with these things is an open circuit earth connection.This is because an OC earth can go un-noticed until someone gets a shock. If the one who gets it is the patient, it could be fatal!
The other is that the bonding resistance from the Earth Reference Bar to the earth point on each device must be less than 200 milliohms, so if you add the resistance of the existing mains lead to the resistance of the extension mains lead, you will probably exceed this value.
The last point is that a standard 13A plug must not carry a total earth leakage current more than 3.5mA. with a number of devices plugged into the socket outlets on the extension, you may exceed this value.

Welcome to the forum, Brian. We look forward to hearing much more from you.

On your last point ... that's why it's nice to have a properly engineered isolated power supply system in the operating theatre, with the LIM bleeping merrily away (it helps to keep the gas-man awake)!

PS: you have an interesting website, by the way. I guess you are already aware than one of the links doesn't work (bottom, left ... a work in progress)?

Sorry about the duff link, I will get round to fixing it one day, but not today!
If anyone would like a copy I can email the Powerpoint on mains extension leads, which is what you would get if the link worked.

... and probably exactly what Mammad needs in order to make his point in the Operating Theatre!

Meanwhile, Brian, do you have any clues about this one?