Looks simple but is quite compicated. First you would need to determine if the conductors are within the range specified by the manufacturer and then check that the fastenings are within the specified torque range. Does that mean that you should losen them and then retighten to the specified torque?

Trust me, it is horrible trying to write standards, often there's no right answer between the precise and the practical. You could say "to a pull force of XXN" and then the response would be "what, I need to attach a force meter to every connection?"  Not to say that what you've posted is ideal, but the challenge is to think of a practical better way of putting it...

A common solution is to make it "sufficiently tight and secure", which is actually no better, just begs the question "sufficient for what?"

My guess is that this is more a reminder to people to at least think about it...

For me - as long as it's not obviously loose - e..g. that a screwdriver won't significantly turn the terminal screw and a light tug on the wire doesn't cause it to move would do.  Tight doesn't necessarily mean some precise torque (I don't believe that initial installation tightening torques are repeatable as testing tor existing anyway) and secure doesn't mean it has to be bomb proof.

   - Andy.

Some items to look for regarding this.

lyledunn said:

how could it be determined that conductors are "tight"?

Get a competent person to do it.

641.6 The verification shall be made by one or more skilled persons competent in such work.

651.5 The periodic inspection and testing shall be carried out by one or more skilled persons competent in such work.

A competent person would know the signs to look for, when you can wiggle conductors (and cannot because of fear or possibility of loosening them ... did someone mention consumer units and fitting of smart meters?), and when and how to use an appropriate (perhaps torque) tool.

In reality, though, in a larger installation, the person installing isn't the person responsible for initial verification ... does this mean that a competent person needs to follow (possibly another competent person) around and re-tighten all of their terminations?

What's worse, is that if you check that box and sign the bottom or accompanying certificate, and it can be demonstrated you didn't check all the conductors were tight, you've not told the truth, which can bring about a whole host of other pain

Just whiz along the terminals with a torque screwdriver. It does not take long!

At which point, I wonder how many sparks have one.

Chris Pearson said:

Just whiz along the terminals with a torque screwdriver. It does not take long!

But doesn't that involve undoing them a little, then re-tightening (i.e.for initial verification, repeating someone else's work, or the work you just did yourself)? I agree the form doesn't specify at what point you did it ... so it might not mean re-checking your own work ... but if you did not recheck your own work, and perhaps keep a "tick box" for EVERY termination, could you, in all honesty, tick the box ?

And ... what about crimp connections, power and data, insulation displacement.

And, of course .... screwless terminals ... you check the lever types by, say pulling the conductor gently, but:

1. Could you say it was "tight" (I would postulate no-one could verify that properly); and
2. What if you accidentally catch the lever when pushing it back into the enclosure, and loosen it?

With either of these, you perhaps lied if you ticked the box?

Begs the question: Why bother ticking the box if the outcome is pretty much impossible to achieve without dropping oneself in it when  someone else comes along picking a fault or other shortcoming in the approach or final application.

There seems to be an unerring approach to making even the simplest things needlessly complicated - paralysis by analysis results, and nothing gets done as a consequence because everyone fears they'll be sued or have other court action taken against them.

whjohnson said:

There seems to be an unerring approach to making even the simplest things needlessly complicated - paralysis by analysis results, and nothing gets done as a consequence because everyone fears they'll be sued or have other court action taken against them.

In BS 7671, it is only 'informative' and in the most pedantic (and pedantry is really where we are in this thread at present ... save the "signing the certificate" issue) sense unnecessary for conformity with the standard ... and, as lyledunn  implies, seems simple at first.

But, it's only 'informative' ... only a real issue for those who are under the burden of anything that sees this as a 'requirement' or who uses it without considering the consequences?

In my opinion, the labeled box displaying outcomes such as C1 etc suggests that this originates from an EICR. As part of your employment for this service, does it not becomes your responsibility/requirement to assess this, wherever possible? Obviously the inspector needs to consider the consequences.