Earthing via Steel Conduit

Question: The existing lighting circuit does not have a earth cable but is earthed through steel conduit, i checked the earth at the furthest position from the board and it was present and below 2ohms. New lighting fittings will be like for like and the fusbox is not being disturbed so can I get away with not installing seperate earth?

Hmm, 'tis a difficult question to answer...

Regardless of how well you know the IET wiring regulations and work accordingly. There will always be a competing electrician who will profit from suggesting that your work is substandard. This is unfortunate but true. By pointing out "flaws" in your work he may well get further work.

As a result, I would always suggest erring on the side of safety, caution & financial security.

I'm assuming that you have better things to do with your time than revisiting previous customers and explaining through detailed tuition, the workings of the IET wiring regulations. Yes, the earth that you have provided via the previously installed steel conduit may be sound but why not play it safe and quote for a full rewire?

If the customer then curses you saying that Mr Polska Electricianz will do the work for half the price, ask them...

Will Mr Polska provide certification for this work?

and Will Mr Polska still be in the country when it comes around to the next periodic test & inspection in five years?

Some may see your work as being an unnecessary rip-off but no-one can accuse you of the greater crime of being unsafe.

This is an everyday crisis of conscience for the hardworking UK Electrician, good luck.