Part 1: The Electrical Installation Certificate (EIC)
The EIC is used for all new electrical installations or for any addition or alteration to an existing circuit (like adding a new socket or replacing a consumer unit). It is a Declaration of Compliance confirming that the work meets the requirements of BS 7671 at the time of energization.
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Procedures for EIC Completion:
Initial Verification: This is a visual check done before testing. You must confirm the correct selection of equipment (e.g., proper IP ratings, kA rating) and the correct erection of the installation (e.g., secure terminations, correct segregation, proper bonding). This ensures the design is structurally sound and safe.
Dead Testing: This battery of tests is performed with the installation de-energized (dead).
Continuity of Protective Conductors: Measure the resistance of all protective conductors and bonding conductors ($R_1, R_2$) to confirm a complete, low-resistance path to the Main Earthing Terminal (MET).
Insulation Resistance: Apply a DC voltage (typically 500V) between conductors (Live to Neutral, Live to Earth, Neutral to Earth) to confirm the integrity of the cable insulation. Readings must be $1 \text{ M}\Omega$ or greater.
Polarity: Confirm that all single-pole devices (fuses, switches, circuit breakers) are connected only in the live conductor.
Live Testing: This is performed with the installation energized (live).
Earth Fault Loop Impedance ($Z_s$): Measure the total resistance of the fault path. The measured $Z_s$ value must be recorded and confirmed to be lower than the maximum permitted value specified in BS 7671 Chapter 41 for the circuit's breaker.
RCD Test: Instrumentally test all RCDs and RCBOs to ensure they trip within the required time limits (e.g., $30\text{ms}$ on a $5\text{x}$ trip test).
Functional Testing: Confirm all circuits, switches, and components operate correctly.
Part 2: The Electrical Installation Condition Report (EICR)
The EICR is a periodic inspection used to assess the condition of an existing installation. It is a Report of Condition, determining whether the installation is safe for continued use and identifying any non-compliances with the current edition of BS 7671.
Procedures for EICR Completion and Coding:
Scope and Extent: Clearly define the limits of the inspection (e.g., "Full inspection up to the consumer unit" or "Inspection of specific circuits 1-5").
Sample Size and Testing: Decide on an appropriate sample size for testing. In larger installations, a percentage (e.g., 10%) of accessory outlets and lighting points are usually inspected visually and tested.
Visual Inspection: Note any wear and tear, physical damage, signs of overheating, or lack of proper earthing/bonding. This is where most faults are identified.
Live and Dead Testing: Perform the same core tests as an EIC ($Z_s$, Continuity, Insulation Resistance, RCD tests), recording the measured values for comparison against the current limits.
Coding the Observations: This is the most critical step. Every deviation from BS 7671 must be assigned one of the following codes:
C1 (Danger Present): Requires immediate remedial action. Poses an immediate threat of electric shock or fire (e.g., exposed live conductors).
C2 (Potentially Dangerous): Requires urgent remedial action. While not an immediate threat, it could easily become dangerous (e.g., no RCD protection on concealed cables).
C3 (Improvement Recommended): Does not pose a danger but does not meet the current standard (e.g., lack of clear labeling).
FI (Further Investigation): Used when the inspector cannot confirm safety without intrusive access or further testing (e.g., uncertain about the type of earthing system).
The final report must clearly state the overall condition: Satisfactory (if only C3s are present or no codes are given) or Unsatisfactory (if any C1, C2, or FI codes are present).
