Extent of Electrical Installations, Limitations & Testing Methods
To verify as far as is reasonably practicable within the limits of this specification that the electrical
installation is in a safe condition and thereby complies with the fundamental requirements of BS
7671:2008, IEE Wiring Regulations 17th Edition and the Electricity at Work Regulations
(1989)/Electricity at Work Regulations (Northern Ireland) 1991.
PURPOSE OF PERIODIC INSPECTION AND TESTING
To provide, so far as is reasonably practicable for:
(i) The safety of persons and livestock against the effects of electric shock and burns
(ii) Protection against damage to property by fire and heat arising from an installation defect
(iii) Confirmation that the installation is not damaged or deteriorated so as to impair safety
(iv) The identification of installation defects and non-compliances with the requirements of the
Regulations which may give rise to danger.
Following careful scrutiny of the installation the inspection and testing will be carried out in
accordance with the recommendations of IEE Guidance Note 3. and BS7671.
To carry out a thorough visual inspection of the electrical installation where practicable with regard
to the following
(b) Wear and tear
(e) Excessive loading (overloading)
(g) External influences
To supplement the visual inspection with such electrical testing as considered necessary for
(a) Electric shock.
(b) Electric burn.
(c) Fires of electrical origin.
(d) Electrical arcing or explosions initiated or caused by electricity.
The inspecting engineer will work with the local users of the installation to ascertain the best times
to power down individual distribution boards during his scheduled time on site.
This disruptive element of the inspection will be for short periods of time at each distribution board. When accesses not available for a distribution board to be powered down, insulation resistance will be verified by testing some of the circuits within that board that will not disrupt the business.
When performing insulation resistance tests, the inspecting engineer will take care to ensure that
any sensitive electronic equipment is safely isolated prior to test. If this is not practicable then
these sensitive areas will not be subjected to this test.
Any limitations to the inspection will be highlighted to the contact daily and included in the report.
(The more limitations a report contains means the suitability of the report to ascertain the safety of
the installation for continued use is placed in question, we would request you allow the inspecting
engineer as much access as possible to perform the inspection)
A full periodic report based upon the model form in Appendix 6 of BS 7671 will be produced
including the following:-
i) Circuit details for 100% of circuits with results of all tests conducted.
ii) All defects categorised into standard priority coding.
DEFECTS AND COMMENTS
The following fault reports detail all defects and non-compliances that were identified during the
Inspection and test.
Each defect has been identified with a priority from 1 to 4.
1: Requires urgent attention
2: Requires improvement
3: Further investigation
4: Does not comply with the current IEE Wiring Regulations. (This does not necessarily imply that
the electrical installation inspected is unsafe.)
Extent of the Electrical Installation Covered by this Report
Distribution Boards & Final Circuits
a) 100% of distribution boards have undergone a thorough visual inspection.
b) 100% of distribution boards have been tested for earth loop impedance and prospective
short circuit current.
c) Approximately 10% of lighting circuits have been tested for insulation resistance.
d) Approximately 20% of power circuits have been tested for insulation resistance.
e) 10% of final ring circuits tested for insulation have had their conductors tested for continuity
where it was practicable.
a) A light fitting in each circuit tested for insulation resistance, has received a thorough internal
b) 100% of lighting circuits tested for insulation resistance have been given an earth loop
impedance test at the furthest point in the circuit wherever it was possible.
c) An additional sample of 5% of all light fittings have been given an earth loop impedance test.
Mains Socket Outlets
a) 100% of sockets have received a thorough external inspection.
b) 100% of socket outlets have been tested for earth loop impedance and polarity.
Fixed Appliances (Not operated from control panels)
a) 100% of fixed appliances have received a thorough external inspection, whilst 10% have
been internally inspected, this included convector heaters fed from fused spurs.
b) 100% of fixed appliances have been tested for earth loop impedance.
c) 10% of fixed appliances have been tested for insulation resistance.
Fixed Appliances (Operated by control panels)
a) 100% of control panels have received a thorough internal inspection where it was possible.
b) Earth loop impedance tests were performed at each control panel, and at each appliance fed
from that panel where it was possible.
c) A 10% sample of electrical terminations inside the control panels have been checked for
RCDs (Residual Current Devices)
100% of RCDs have been tested for tripping time at half rated, full rated, and five times rated tripping current, across positive and negative cycles.
Main Switchgear & Circuits
20% of all circuits (sub mains) from main switchgear to local distribution or dedicated plant has been
inspected for the following:-
a) Insulation resistance.
b) Main switchgear has been internally inspected.
c) Cable sizes have been checked for current carrying capacity.
d) Circuit protection devices have been checked for discrimination.
e) Earth loop impedance & prospective short circuit current have been measured as close to the
origin of the earth supply as possible.
100% of circuit wiring have where possible and relevant been visually inspected.
a) Where earth loop impedance test results are above that specified in IEE Wiring Regulations,
CPC/50 volt drop calculations have been carried out where it was practicable.
b) 100% of fixed appliances/plant not subject to an insulation test, may have been given an earth
loop impedance test using a different R1 (phase conductor) from that used to supply the
Limitations & Exclusions
Testing and inspection has been undertaken where it was reasonable and practical to do so, without
dismantling the fabric of the building.
Areas and systems that were not considered are:-
a) Heating and ventilation equipment and controls.
b) Security, fire and door entry systems.
c) Refrigeration Equipment.
d) Any circuits incorporating solid state controls.
e) Point of Sale Equipment.
Inaccessible sockets for refrigeration.
g) No insulation resistance readings to be completed on lighting circuits which are controlled via trend on any other BMS controlled system within installation (if applicable)
h) No testing of lift services and shaft areas
g) No testing of Fire and Alarm circuitry beyond original supply source and testing of plant services from isolation point unless otherwise instructed by client
h)No testing of sub mains to tenants services within installation
i) No Lifting of floor boards or inspection of loft space.
j) No testing of HVAC control cables. Routing of cables in prescribed zones or within mechanical protection.