You are not clear exactly what routine checks you have in mind, nor on what, nor where. Combined, these add enough uncertainty that anything from ' almost never needs checking' for some remote thing with a very simple installation that is not that critical anyway, like the light and switch  in a remote locked substation cabin only ever visited by skilled persons, to 'needs checking once a week' for some equipment  in a place where abuse is likely and the consequence of a failure almost intolerable - certain types of industrial environment can be very rough on connectors and switches.

Mike.

And in a new or modified installation, perform a basic check on ALL the lights. Can all the lights be turned on by switches suitably placed ? Can all the lights be turned off by suitably placed switches. This may sound elementary, but I have often found some lights that cant be turned on or off.

Then check that every general purpose socket outlet actually works, as a minimum use a plug in socket tester, followed by a fan heater. In a newly built office, I found several 13 amp sockets with no supply(plugged into underfloor busbar trunking, not enough busbar outlets, so end sockets not connected.) and others wrongly wired (earth and neutral reversed, revealed by the instant tripping of the RCD when using a heater.)

the routine checks I am referring to are those stated on page 84 of guidance note 3 of BS7671. Agree they can be applied to a whole range of installations and environments which is why I was asking what are peoples’ thoughts or approaches to managing these. Do you carry out and document all routine checks? Or is it risk based and some routine checks are not competed? 
I mentioned both industrial environments and buildings and the different approaches.

Agree an industrial storage shed is more likely to be damaged where as a building less likely to be damaged if in segregated areas but the building occupies people so is higher risk. I am aware it is not black and white I was just looking for people’s experience of approaches and how they manage these routine checks. 

Do you carry out and document all routine checks? Or is it risk based and some routine checks are not competed? 

Jein.

as in both yes, sometimes; and no, sometimes.

Realise that neither GN3 nor the wiring regs are statutory requirements except in a few exceptional situations. Legally and sensibly, however, you will want to ensure a comparable level of safety by any other route.

I'd not really expect an electrician to be the person looking for damaged extension leads and broken fittings and so on, that can be almost anyone competent to do so, and maybe in a works setting, suitably instructed users can look for and report that sort of problem every time the use the thing, and in certain cases that approach makes more sense than waiting with  a dangerous state of affairs, for the next formal tour of inspection. 

If the users are not able to do this, then a more formal inspection by a named person and a suitable interval needs to be agreed.

But to convince those who read without understanding, if the actual results are not documented then instead record exactly who has been asked to look out for things, and who and how they have been told to report things to if something is spotted. Make sure that the right folk do understand that they have persmission to make the decision to turn something off  or to call for assistance if it is doing something funny.

It may well be that a full covers off and meters out documented inspection every 5 years or whatever is fine, so long as in the meantime there is a clear 'spot it- switch it off, report it!' process for things that go wrong in between even if there are very few or even no formal routine inspection tours at all, just an ongoing 'constant vigilance' .

Equally some places have more skilled persons than general public, and the risk levels are then very different, not less mind you, just different.
(A little knowledge is a dangerous thing, consider what a lot of it may do... )

Guidance is just that,  and very often the approach must  be tailored to suit the circumstances.

Oh and I'd not get that cut up about a year or 2 years or half a year or indeed any other interval of choice either. The log of repairs will tell you how often stuff goes wrong.

Mike.