Code 4 means it does not comply with current edition of BS7671 and really is a warning that if you have alterations this will likely need up-grading.
Code 2 means although no immediate danger any secondary fault could make it a danger. However "No labelling of switches and protective device" could hardly fall into that category but since it is not code 1, 3, or 4 no real code for this fault so I can understand the code 2.
I would hope he has said where the notices are required. Where two editions of BS7671 are used a notice of colour change is required. Where a RCD is used a notice to test regular is required. And all MCB's should be labelled as to what they control.
So likely some all all of following are missing there is a minimum size but either you can buy ready printed labels or even hand write to comply.
514.1.1 Except where there is no possibility of confusion, a label or other suitable means of identification shall be provided to indicate the purpose of each item of switchgear and controlgear. Where the operator cannot observe the operation of switchgear and controlgear and where this might lead to danger, a suitable indicator shall be fixed in a position visible to the operator.
514.13.1 A permanent label to BS 95 1 with the words "Safety Electrical Connection - Do Not Remove" shall be permanently fixed in a visible position at or near:
(i) the point of connection of every earthing conductor to an earth electrode. and
(ii) the point of connection of every bonding, conductor to an extraneous-conductive-part, and
(iii) the main earth terminal, where separate from main switchgear.
This installation should be periodically inspected and tested and
a report on its condition obtained, as prescribed in the IEE
Wiring Regulations BS 7671 Requirements for Electrical
Date of last inspection.....................
Recommended date of next inspection.............................
This installation, or part of it, is protected by a device which
automatically switches off the supply if an earth fault develops.
Test quarterly by pressing the button marked `T' or `Test'. The
device should switch off the supply and should then be switched
on to restore the supply. If the device does not switch off the
supply when the button is pressed, seek expert advice.
on the report should be an explanation of the codes.
1=requires urgent attention, circuit must be disconnected until rectified.
3=requires further investigation.
4=does not comply with current regs.
Your code 4's = no "warning 230 Volts" sticker on consumer unit etc
he could also mean other such statutory labels missing. he should have been more specific.
Your code 2's,
The switched lives/lines at switches and lights have not been correctly colour sleeved eg black or blue cores at switches lights should have been sleeved with red/brown to show they are not neutrals.
If this had been done it would prevent about 10% of the questions asked on here when people try to change light fittings and get sw-lines mixed up with Neutrals!
Labeling of protective devices might mean the fuses/mcb's not marked as to what circuits they supply, I am surprised at this one as in order to do his tests he would need to find that out in order to complete the schedule of tests page of the PIR.
Code 3 rarely used in domestic situation, only time I have used it is when turning off a circuit appears to have no effect, I leave it off until customer complains about loss of power to some obscure item, Bingo! circuit located.
N.A.P.I.T. registered so do many I&T jobs.
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