3.2 Compiling the Schedule of Inspections for Existing Installations
Key Takeaways
- The Schedule of Inspections for existing installations utilizes standard outcome symbols: tick (✓) for Acceptable, 'C1' (Danger present), 'C2' (Potentially dangerous), 'C3' (Improvement recommended), 'FI' (Further investigation required), 'N/A' (Not applicable), and 'LIM' (Limitation).
- Every C1, C2, C3, or FI code marked on the Schedule of Inspections MUST be supported by a corresponding itemized observation narrative in Section K of the EICR.
- Visual inspection of existing installations requires assessing degradation, damage, corrosion, overload, environmental suitability (IP rating, ambient temperature, mechanical impact), and departure from current BS 7671 editions.
- Inspection checklist categories cover incoming supply head, consumer units/distribution boards, final circuits, identification/labeling, protective bonding, and special locations (e.g. Section 701 bathrooms).
- Enclosure IP requirements mandate IP4X (or IPXXD) for top horizontal surfaces of consumer units and IP2X (or IPXXB) for side and bottom surfaces to prevent accidental contact with live parts.
3.2 Compiling the Schedule of Inspections for Existing Installations
The Schedule of Inspections is a mandatory element of an Electrical Installation Condition Report (EICR). As specified in BS 7671 Appendix 6 and IET Guidance Note 3 (GN3), the inspection schedule for an existing installation provides a systematic checklist designed to evaluate whether the physical infrastructure has deteriorated, suffered damage, or been modified in a manner that compromises safety. Unlike initial verification (where inspection confirms compliance with the design of a new build), periodic inspection evaluates existing equipment against the safety standards of the current edition of BS 7671, taking into account normal operational wear and tear.
Standardised Inspection Outcome Symbols & Notation
When completing the Schedule of Inspections, inspectors must record an explicit outcome code for every single listed item. Leaving blank boxes is strictly prohibited and invalidates the report.
+-----------------------------------------------------------------------------------+
| INSPECTION SCHEDULE OUTCOME SYMBOLS (GN3) |
+--------+------------------------------------+-------------------------------------+
| SYMBOL | MEANING | ACTION REQUIRED |
+--------+------------------------------------+-------------------------------------+
| ✓ | Acceptable | Meets current BS 7671 safety standards|
| C1 | Danger Present | Immediate remedial action required |
| C2 | Potentially Dangerous | Urgent remedial action required |
| C3 | Improvement Recommended | Non-dangerous departure from BS 7671|
| FI | Further Investigation Required | Investigate without delay |
| N/A | Not Applicable | Item does not exist in installation |
| LIM | Limitation | Agreed or operational limitation |
+--------+------------------------------------+-------------------------------------+
Rules for Outcome Code Mapping
- Every box marked with C1, C2, C3, or FI on the Schedule of Inspections MUST correspond to a uniquely numbered, detailed observation narrative in Section K of the EICR.
- When an item cannot be inspected due to an agreed or operational limitation, LIM must be entered in the box, and the exact constraint described in Section D.
- If an inspection category does not exist within the premises (e.g., item 7.0 Special Locations in an office with no bathroom or shower), N/A must be entered.
Itemised Breakdown of Primary Inspection Headings
Guidance Note 3 structures the periodic inspection checklist into primary technical categories:
1.0 Intake Equipment (Service Head & Origin)
Inspectors must perform a thorough visual audit of the DNO intake equipment at the origin of the installation:
- Service Cable & Cutout: Visual check for signs of thermal damage, tracking, arcing, or mechanical breakdown. Note: Inspectors must never break DNO seals or open the service cutout.
- Cutout Meter Tails: Sizing verification (typically $25mm^2$ copper for 100A domestic intake), insulation condition, and support.
- Isolator & Meter Enclosure: Presence of a double-pole main isolator at the origin. Checking that intake equipment is securely mounted and protected against environmental ingress.
2.0 Presence of Warning Notices & Identification Labels
BS 7671 mandates specific durable warning labels across the installation:
- Main Earthing & Bonding Labels: BS 951 safety labels ("Safety Electrical Connection - Do Not Remove") fitted at all main protective bonding conductor connections to extraneous-conductive-parts.
- RCD Test Label: Periodic test notice fitted at or near consumer units containing RCDs, advising the user to test the device periodically via the integral test button.
- Dual Supply Warning: Warning notice where an installation contains alternative or standby power sources (e.g., PV solar inverters, generators, battery storage).
- Non-Standard Conductor Colours: Warning notice where existing installations contain legacy conductor colours (e.g., pre-2004 red/black mixed with harmonized brown/blue).
- Next Inspection Label: Durable notice affixed near the main distribution board stating the recommended date for the next periodic inspection.
3.0 Consumer Units & Distribution Boards
Distribution equipment represents the primary area for visual inspection of electrical containment and safety:
+-----------------------------------------------------------------------------------+
| CONSUMER UNIT INGRESS & SAFETY INSPECTION CRITERIA |
+-----------------------------------------------------------------------------------+
| TOP HORIZONTAL SURFACE: Minimum IP4X / IPXXD (No openings > 1.0mm) |
| SIDES & BOTTOM SURFACES: Minimum IP2X / IPXXB (No openings > 12.5mm / fingers) |
| ENCLOSURE MATERIAL: Non-combustible (Steel) for domestic (Reg 421.1.201) |
| BLANKS & COVERS: No missing module blanks; live parts fully enclosed |
+-----------------------------------------------------------------------------------+
- Enclosure Integrity: For domestic installations, consumer units must be manufactured from non-combustible material (steel) or enclosed in a non-combustible cabinet complying with Regulation 421.1.201 to contain internal fires.
- Ingress Protection (IP Ratings): Top horizontal surfaces of readily accessible consumer units must achieve IP4X or IPXXD (preventing ingress of solid objects $\ge 1.0mm$, such as small wire). Side, rear, and bottom surfaces must achieve IP2X or IPXXB (preventing ingress of objects $\ge 12.5mm$, such as fingers).
- Circuit Identification: Complete and accurate labeling of all MCBs, RCBOs, and fuses, detailing circuit designation, conductor size, and protective device rating.
4.0 Final Circuits & Environment
- Conductor Sizing & Protection: Correct coordination between conductor current-carrying capacity ($I_z$), design current ($I_b$), and protective device rating ($I_n$) such that $I_b \le I_n \le I_z$.
- Additional Protection: Verification that RCD additional protection ($I_{\Delta n} \le 30\text{mA}$) is provided for socket-outlets rated up to 32A, mobile equipment used outdoors, and AC final circuits in locations containing a bath or shower.
- Routing & Mechanical Protection: Cables concealed in walls at a depth of less than 50mm must run in prescribed safe zones (horizontally or vertically from accessories, or within 150mm of wall tops/corners) or incorporate earthed metallic armouring / earthed conduit.
5.0 Special Locations (BS 7671 Part 7)
Inspection of special installations—such as locations containing a bath or shower (Section 701)—requires strict adherence to zone boundaries (Zone 0, Zone 1, Zone 2):
- Verification that all low-voltage final circuits passing through or serving equipment in Zone 1 or 2 are protected by a $30\text{mA}$ RCD.
- Checking IP ratings of luminaires and accessories in Zone 1 (minimum IPX4, or IPX5 where water jets are used for cleaning).
During an EICR inspection of an existing commercial installation, every item on the Schedule of Inspections must be completed with an outcome symbol. What is the consequence of leaving blank check-boxes on the schedule?
What is the minimum IP rating required for the top horizontal surface of a domestic metal consumer unit under BS 7671?
While visually inspecting a domestic cutout intake head, an inspector notes that the main service head casing is cracked, exposing uninsulated live service conductors. How should this be documented and handled?
An inspector observes that a main protective bonding clamp on a gas pipe lacks a BS 951 safety warning label ('Safety Electrical Connection - Do Not Remove'). The bonding conductor connection itself is tight and low resistance. What observation code should be assigned in Section K?