Zoomup: 
 

JDW: 
 

Are 5amp junction boxes acceptable on a 6amp lighting circuit?

I personally wouldn’t use them as they are too small, but if they are already fitted are they acceptable? 

Oh yes. The rating is only nominal. You say “already fitted.” Fitted to what?

Z.

I worked with an electrician who always used them on lighting circuits with 6a breakers, is this common practice on domestic properties?

Zoomup: 
 

JDW: 
 

Are 5amp junction boxes acceptable on a 6amp lighting circuit?

I personally wouldn’t use them as they are too small, but if they are already fitted are they acceptable? 

Oh yes. The rating is only nominal. You say “already fitted.” Fitted to what?

Z.

I worked with an electrician who always used them on lighting circuits with 6a breakers, is this common practice on domestic properties?