Isolating neutrals, working live?

[Aaron b]

Hi, where only single pole isolation is achievable and a shutdown is problematic, what is the best practice with neutrals when connecting and disconnecting circuits?

I understand that all live conductors should be isolated and we shouldn't work live, but out of the class room it is not always achievable. Is it really a risk and does anyone insist on full isolation?

What is the mechanism in which the neutral becomes dangerous? Is it loss of the dno neutral?

Many thanks

 

[James]

One of the classic fails would be on a lighting circuit.
leave the breaker on but turn the light switch off.

you may have a permanent live at the light fitting but even if not, separating the neutrals my lead to one of them becoming live being fed from another light with no return path.

 

[Aaron b]

...you may have a permanent live at the light fitting but even if not, separating the neutrals my lead to one of them becoming live being fed from another light with no return path.

Ah I hadn't thought of that one.

I haven't worked with anyone competent for a while so I don't have much basis on what's generally done. Some things are a little difficult to write in risk assessments too.