The problem is that things like safe shock current and duration are very Physiology dependent.

A vet specialising in primates or pigs may well read across what is needed from humans, but some one doing mostly cats or birds probably cannot. Disconnection times ought to scale with heartbeat period, so smaller animals like mice will go into fibrillation in a far shorter time than elephants or heavy horses. (I do not have a good reference for that.)

The choice has to be driven by the medical considerations  - BS7671 being written by electrical subject matter experts, therefore, quite correctly says nothing beyond "refer to the experts".

The whole zone groups and shock levels thing is really derived for humans on the operating table and assuming a  human heart and lungs, As soon as this assumption is invalid so is the rest.

By all means use the 710 material as a starting point but do not get hung up if it ends up being decided that something else, or even no special measures at all, makes more sense.

Mike.

mapj1 said:

so smaller animals like mice will go into fibrillation in a far shorter time than elephants or heavy horses

Strange thing is that fibrillation (of atrium or ventricle) can be fixed by a shock. Trust me, I have had it done!

Hi Chris, I’m sorry to hear that you had to go through such a frightening experience. Fibrillation is a serious condition that can affect the heart’s ability to pump blood effectively. I’m glad that you were able to receive the treatment you needed and that you are doing well now.

AMK, thank you. Atrial fibrillation, which I had is more of a nuisance than anything else; ventricular fibrillation (which can occur after an electric shock) is fatal if not treated within a few minutes. That's why defibrillators are carried in ambulances, etc.

My experience was not at all frightening because it was used for the former. The irritating bit was that the cardiologist insisted on sedation so I was not conscious at the time and experienced nothing.

According to the commentary on BS 7671 book, the timing of the shock in relation to the cardiac cycle is a critical factor for the outcome. For example, if the shock coincides with a certain point, it can induce ventricular fibrillation, which as you described is a condition where the ventricles of the heart tremble instead of contracting blood. This is a life-threatening situation that requires urgent defibrillation. However, was it a shock that caused your atrial fibrillation ?  (atria of the heart beat irregularly). So this is what You experienced ? and did you undergo a procedure called cardioversion to correct it ? (low-energy electric shock that is synchronized with the heart’s natural rhythm) but has anyone ever experienced an electric shock? How did it affect you? What did you do about it?

AMK said:

has anyone ever experienced an electric shock? How did it affect you? What did you do about it?

Slightly closer to the original thread ...

My first was at the age of about 8. We had lamps attached to the bed head and they were operated by a switch on a dangling bit of flex. Mine fell off in the night so when I reached up in the morning I touched a live cable. I have never before or since least out of bed so quickly.

My most recent time was when re-wiring daughter's house. I could not isolate the whole installation because she and other tradesmen wanted power, but I had isolated the downstairs lights and proved dead. Problem was that one of the light switched was connected to a different circuit. I swore!

(The place was a potential death trap - one ordinary sized room had sockets powered by three different circuits.)

Apart from the obvious learning point about proving dead all the time, I think that the experiences were merely unpleasant because I was somewhat insulated from the general mass of the earth and I was able to let go.

I experienced my first electric shock when I was a 17-year-old apprentice. I was assigned to replace a socket in a pub kitchen. I verified that the socket was not live and proceeded to disconnect it. I had both ends of the ring line conductor in my hands, when suddenly I felt a jolt of pain. I heard a loud scream and wondered who was making such a racket, only to realize that it was me. The electrician I was working with had turned the circuit back on without warning me! It was a shocking experience, literally and figuratively. 

I experienced my first electric shock when I was a 17-year-old apprentice. I was assigned to replace a socket in a pub kitchen. I verified that the socket was not live and proceeded to disconnect it. I had both ends of the ring line conductor in my hands, when suddenly I felt a jolt of pain. I heard a loud scream and wondered who was making such a racket, only to realize that it was me. The electrician I was working with had turned the circuit back on without warning me! It was a shocking experience, literally and figuratively.