EICR - Extent of Sampling

[DefyG]

Had an enquiry where the installation (commercial) is relatively new and client has requested a condition report.
Probably 80-100 circuits plus distribution circuits etc in total.
Client has suggested to me (not sure where it came from, another sparks possibly?) and probably driven by overall cost of testing 100+ circuits that if say 25% of circuits tested were found to be satisfactory and that as the installation was done all at same time to same standard by same company, the client would be happy to accept a satisfactory EICR on the basis that the installation as a whole would also be satisfactory.

We've always worked on the basis that final circuits are 100% tested and sampling of say 25-30% of accessories/cabling/connections etc (bar any operational limitations) but if Part 7 boxes (NICEIC - EICR) 'Limitations and Extent of Sampling' are filled in appropriately would a report of the whole, based on a circuit sample of say 25% still be considered 'satisfactory'?
I suggested that any non-compliance found in say the first 25% would necessitate further testing over and above the 25% with further non-compliances leading towards 100% testing!
Would you be happy to put your name to that?


Thoughts?

 

[plugsandsparks]

Never done cct based sampling, its going to make the reports sheets look "strange" and how do you determine for sure what cct goes where with what load. Even though its brand new does not mean it was installed satisfactory in the first place.

If its new and commercial, should not be too difficult to locate all 100 of ccts.

So i guess the answer from me is no, its 100% of ccts

Good Luck

P&S

 

[westward10]

I don't have a problem with this and it will be noted in the Limitations, the Report only applicable to those circuits tested. Assuming the 25% sample is satisfactory you cannot assume the remaining 75% is the same and do not suggest this, if the client wishes to use the 25% as the basis for the whole that is their decision.

 

[DefyG]

how do you determine for sure what cct goes where with what load

On the assumption that the 25% tested are correct?

Even though its brand new does not mean it was installed satisfactory in the first place.

Agreed, Its not brand new but have seen the EIC and it has all been done to a good (high) standard.

should not be too difficult to locate all 100 of ccts.

Agreed but I guess the client is looking at costs from the conversations we've had.

Assuming the 25% sample is satisfactory you cannot assume the remaining 75% is the same

That is what they are hoping for due to the standard of workmanship but it would be my name on the report!

 

[westward10]

You make it clear the scope of the Report. I quote something along the lines of this Report is only applicable to the circuits on the attached schedules. Advise the client you can only comment on what has been tested and the condition of the remainder can only be speculation something you are not willing to do.

 

[plugsandsparks]

Have to reply - What is the point ? - So client says i have £3.50 to spend on a report, want a satisfactory, choose the best ccts, lol

That report i would throw in the bin and am surprised anyone would accept a cct sheet showing 48way board with 12 ccts filled in , the rest limitations... what a joke

 

[Julie.]

With commercial, it is quite common to perform fairly small samples, the point is unlike domestic they will often have someone responsible for the planning of the scope of work. This person will often phase the inspection work over several years.

In simple terms, main supply and building A in year one, backup supplies and building B the next year... and so on until over say 5/10 years the whole site has been inspected and it starts again.

(On smaller sites, it's usually on a circuit basis, so rather than one big inspection basically shutting the site down once every 5 years they have 5 smaller yearly inspections allowing the site to remain working - the end result is "everything" tested every 5 years, just not everything together!)

This sounds like they are looking for an overview of the current state of the installation, from which they can plan the formal testing regime.

 

[plugsandsparks]

Thats basically how i have done the larger sites, usually by substation. So start at sub 1, flow out to MDBS and onto DBs, finish that section and then later move onto Sub 2 etc until the whole site is done. On the bigger sites, for the employee electricians i provide a "interim list of Code 1,2" - and if they are available , they correct the installs as i go along. As most of the C1,C2 are either broken accessories, damaged cables or incorrectly designed installs (out of spec Zs) - Testing a sample simply does not fit my method of testing, i.e. what do you do when you spot a damaged cable or accessory on a cct you are not testing, just ignore it ?
What i do is photograph it (so they know where to look) and hopefully its fixed before i leave that week otherwise the code stands.
Where there are no local electricians, i correct as many as i can for the time i have allowed. Then arrange a re-visit.

So i dont have a conversation about "sampling" - this never happens - the client wants the install to be satisfactory, not 25% satisfactory and who knows about the rest.

the conversations i have are more about keys, access, moving product out of the way, alarms, IT equipment, very high level lighting and shift patterns for downtime.

 

[cliffed]

You are allowed a sampling process, i feel it would be impossible to I&T every point.
If the client is prepared to pay for that so be, you can use your experience to know how the installation will go either satisfactorily or unsatisfactorily.
Usually DB 100% 100% final distribution circuits 100% final circuits & anything from 50% to 100% on accessories/equipment making niotes on what’s been tested.
Like above comments, next time the remaining items tested next time around