What do you consider a sample to mean during an EICR

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What has been inspected and tested would have been agreed with the client before starting work on site. What has been inspected and tested should be set out in the "Extent" box in some detail to show what has been inspected and tested and what has not. Also  included in the "Limitations" will be the agreed exceptions to what has been inspected and tested.

Chris

If testing a 100 bed hotel you would agree with the client  before work starts what the extent and limitations are to the work. If I&Ting the whole hotel in one hit you may want to use the same method of testing the rooms as set out in my spec. for dwellings. They use a small consumer unit for each room or pairs of rooms with a 3 phase DB at the ends of the corridors either 1 DB or 2 DBs for a long corridor. The DBs being supplied from  a panel board. If not doing the whole hotel in one year maybe over  5 years with 20% a year agreed with the client. If there is a swimming pool present then the swimming pool every year. Industrial kitchens maybe every 3 years.

651.1 mentions previous documentation and the absence of documentation. IET GN3 provides extensive guidance on periodic inspection and testing.A standard textbook for inspectors in my view.

Zoom

What has been inspected and tested would have been agreed with the client before starting work on site. What has been inspected and tested should be set out in the "Extent" box in some detail to show what has been inspected and tested and what has not. Also  included in the "Limitations" will be the agreed exceptions to what has been inspected and tested.

Chris

If testing a 100 bed hotel you would agree with the client  before work starts what the extent and limitations are to the work. If I&Ting the whole hotel in one hit you may want to use the same method of testing the rooms as set out in my spec. for dwellings. They use a small consumer unit for each room or pairs of rooms with a 3 phase DB at the ends of the corridors either 1 DB or 2 DBs for a long corridor. The DBs being supplied from  a panel board. If not doing the whole hotel in one year maybe over  5 years with 20% a year agreed with the client. If there is a swimming pool present then the swimming pool every year. Industrial kitchens maybe every 3 years.

651.1 mentions previous documentation and the absence of documentation. IET GN3 provides extensive guidance on periodic inspection and testing.A standard textbook for inspectors in my view.

I worked in a large production factory once. It had several teams of fully qualified 24/7 maintenance electricians whose primary job was to keep the production machines running. If a fault developed on an individual machine, or a row of machines or a row of overhead lights, a team member would immediately be dispatched to investigate and hopefully repair the problem.

I believe that the whole installation was constantly inspected and tested most of the day and night on an ongoing basis. Faults just were not allowed to exist for long. Shut downs were not possible.

Definition. Sampling is a process used in statistical analysis in which a predetermined number of observations are taken from a larger population. The methodology used to sample from a larger population depends on the type of analysis being performed, but it may include simple random sampling or systematic sampling.

Edit. Add, I only have Guidance Note 3 for the 17th edition. SHOCK HORROR. But I can't see that it differs much from the newest version.

Table 3.3 suggests minimum sample sizes for inspection:

Main switch gear external inspection.

Main switchgear internal sections and cable terminations.

Main switchgear internal inspection of circuit breakers and control sections.

Final circuit distribution boards.

Earthing and protective bonding conductors.

All 100 per cent to be sampled.

Then.......

Final circuit accessories between 10 to 100 per cent.

Z.