Common Causes of CoC Rejection and How to Prevent Them

That Certificate of Compliance (CoC) is your golden ticket when selling your home or renting out your property. It’s the document that unlocks the deal, finalises the sale, and gives everyone peace of mind. But what happens when the electrical inspector slaps a big 'REJECTED' on your application? Suddenly, you're facing delays, unexpected costs, and a great deal of stress. A CoC is more than just a piece of paper; it's a legally required document that certifies the electrical installations in a property are safe, legal, and fully compliant with the stringent South African National Standard, SANS 10142-1. Without it, property transfer grinds to a halt, and insurance companies may refuse to pay out in the event of an electrical fire. This guide will walk you through the most frequent reasons for CoC rejection, providing you with clear, actionable steps to identify and rectify these issues before the inspector arrives, saving you time, money, and a significant headache.

The Foundation: Understanding the Law & The Inspector's Role

Before we dive into the specific faults, it's crucial to understand the "why" behind the inspection. The CoC isn't based on an inspector's personal opinion; it's a legal requirement under the Occupational Health and Safety Act (OHSA) 85 of 1993. The specific rules for electrical installations are detailed in SANS 10142-1:2020 - The wiring of premises. This standard is the electrician's and inspector's bible. When an inspector issues a CoC, they are putting their name and their wireman's license on the line, legally stating that the installation is safe. They assume liability for its safety. Therefore, they are not being difficult or nitpicky; they are performing a critical, legally-mandated duty to prevent electrocution, electrical fires, and other hazards. Understanding this context is the first step in appreciating why the standards are so non-negotiable.

Missing or Inadequate Documentation: The Paperwork Pitfall

You might have the safest electrical installation in the country, but if the paperwork isn't in order, your CoC application will be rejected before the inspector even lifts a tester. Administrative errors are a leading cause of immediate and easily avoidable rejection.

The most common documentation failures include an incomplete or incorrectly filled-out CoC form itself. Every section must be accurately completed and signed by a registered electrician. Another critical piece of paperwork is the single-line diagram. This schematic of your electrical system must be clear, legible, and show the distribution board (DB) layout, all circuit breakers, and their designated areas (e.g., "Geyser," "Kitchen Plugs," "Outside Lights"). Finally, the electrician must be able to provide proof that all components used—from the cables to the circuit breakers and plugs—bear the SABS mark or a valid Letter of Authority (LOA). This confirms they are approved for use in South Africa.

Preventive Remedies:

• Ensure your electrician uses the latest, standardized CoC form.

• Insist on a detailed, legible single-line diagram of your electrical system.

• Keep invoices that specify the SABS-approved materials used in any new work.

The Heart of the System: Distribution Board (DB) Defects

If the electrical system is the body of your property, the Distribution Board (DB) is its heart—and it's the most scrutinised component during an inspection. A messy, poorly maintained DB is a major red flag.

Inspectors will immediately check for clear and permanent labelling on every circuit breaker. Illegible scribbles or, worse, missing labels entirely are a common fault that will result in a failure. Inside the DB, sloppy, tangled wiring poses a serious fire and short-circuit risk. Cables must be neatly routed, secured, and organised. Furthermore, each circuit breaker must be correctly sized to protect the cable it serves. For example, a 2.5mm² cable must be protected by a 20A breaker, not a 30A, as an oversized breaker won't trip during an overload, causing the cable to overheat and potentially ignite.

The most dangerous fault of all is an unauthorised modification. "Dangerous and illegal DIY connections, like bridging out a faulty breaker with a piece of wire—a notorious 'loop'—will result in instant failure and represent an extreme fire hazard," warns a seasoned Johannesburg-based inspector.

Preventive Remedies:

• If your old DB is a tangled mess, invest in a new, modern one with clear, professional labelling.

• Hire a qualified electrician to re-wire the DB internally for neatness and compliance.

• Under no circumstances should anyone other than a qualified electrician ever modify the DB.

Life-Saving Protection: The Non-Negotiables of Earth Leakage Protection

The Earth Leakage Protection Device (ELPD or RCD - Residual Current Device) is a critical life-saving device designed to prevent fatal electric shocks. Its proper operation is non-negotiable for a CoC.

A working earth leakage device, typically with a sensitivity of 30mA or less for socket outlets, is mandatory and must be installed at the origin of the installation. During the inspection, the inspector will press the test button. If the device does not trip and cut all power to the relevant circuits, it is an automatic failure. It's not enough for it to just trip; it must trip within the required time, which is typically 300 milliseconds for a 30mA device. A slow trip indicates a failing unit or problems within the circuit.

Many older properties have earth leakage devices that have never been tested and have seized up over time, leading to an immediate CoC rejection. A common and dangerous practice is when a homeowner or unqualified handyman bypasses the device because it "nuisance trips," instead of diagnosing and fixing the underlying fault, which is often a latent and dangerous earth leakage current.

Preventive Remedies:

• Test it monthly. Make pressing the test button a regular household habit. If it doesn't trip, power is not cut, or it feels sluggish, contact an electrician immediately.

• Never allow anyone to bypass the earth leakage unit for any reason.

• Ensure the device is the correct type and rating for your specific installation.

A Solid Ground: The Critical Role of Earthing and Bonding

While the earth leakage device protects against shock, a proper earthing system is the silent, fundamental guardian of your entire electrical installation. It provides a safe path for fault current to travel, ensuring that a circuit breaker will trip in the event of a fault.

The property must have a functional earth electrode (an earth spike) driven into the ground, with a sufficiently low resistance reading. The acceptable value varies by area and system type, but in urban TN-C-S systems, it is typically required to be below 1 ohm. Inspectors use specialised earth loop impedance testers to verify this. The earth conductor must then be continuous and securely connected from the DB to all earth points throughout the property, including every plug outlet and metal light fitting.

A frequently overlooked aspect is bonding. This involves connecting all exposed conductive parts—like metal water pipes, gas pipes, and even the metalwork in your bath or shower—to the earth system. This "equipotential bonding" prevents a dangerous voltage from appearing on these metal parts if a fault occurs elsewhere.

Preventive Remedies:

• Have an electrician measure the earth resistance with the proper equipment. A visual check of the spike is not enough.

• Visually inspect the main earth wire where it enters the DB for signs of damage or corrosion.

• Ensure all bonding is in place, a point particularly important to check after any plumbing work has been done.

Outlets & Switches: Common Installation Errors

The plug points and light switches you use every day are frequent failure points during a CoC inspection. What seems like a minor issue can signify a major safety hazard.

One of the most dangerous and common faults is incorrect polarity. This occurs when the "live" and "neutral" wires are reversed in a plug socket. While a device plugged into such a socket may still work, it remains "live" even when switched off at the device, creating a severe shock risk. All 3-pin sockets must have a functional earth connection. Older, 2-pin sockets are completely non-compliant and must be replaced. In "special locations" like bathrooms, sockets must be a safe distance from water sources (at least 1 meter from a bath or shower) or must be a dedicated, isolated shaver socket. Finally, simple wear and tear, such as cracked socket faces, loose switches, or visible wiring, are immediate red flags for an inspector.

Preventive Remedies:

• Invest in a cheap and simple plug tester from your local hardware store. It will instantly tell you if your sockets are correctly wired.

• Proactively replace all old, damaged, or loose sockets and switches.

• Ensure any sockets in bathrooms or outdoors are the correct, compliant type for that wet or damp environment.

Cable Crimes: Incorrect Selection and Installation

The cables hidden in your walls and ceiling are the veins and arteries of your electrical system, and faults here are a leading cause of electrical fires.

Using an undersized cable for the electrical load is a critical error. For instance, using a thin 1.5mm² cable for a stove circuit that requires a 6mm² or 10mm² cable will cause the cable to overheat under load, melting the insulation and creating a fire risk long before the breaker trips. Cables must also be securely clipped or supported along their entire run; they should not be left dangling from roof timbers or buried under insulation. Using the wrong type of cable for the environment is another common issue. Standard PVC cable cannot be used outdoors where it is exposed to UV degradation and moisture, nor should it be used in a ceiling where it is in direct contact with thermal insulation, as it will overheat.

Furthermore, all joints and connections must be made inside approved junction boxes, accessible for inspection. The old practice of twisting wires together and covering them with insulation tape is illegal and incredibly dangerous.

Preventive Remedies:

• Ensure your electrician uses the correct SABS-approved cable type and size for each specific circuit.

• Take a torch and inspect your roof space for poorly installed, dangling, or damaged cables.

• Never allow "illegal" joints; insist that all connections are made within proper, enclosed junction boxes.

Lighting Loopholes: Overlooked Faults in Light Fittings

It's easy to assume that if the lights turn on, they are compliant. However, lighting circuits and fittings often hide faults that can lead to CoC rejection.

A very common fault, especially in older homes, is the lack of earthing on metal light fittings. Whether it's a pendant, a downlighter, or a decorative fitting, if it's made of metal, it must be earthed. A missing earth wire here is a direct shock hazard. Another significant fire risk involves downlighters, particularly the older halogen types. These fixtures generate intense heat and must have sufficient clearance from ceiling timbers and insulation. When buried under insulation, they can overheat to the point of igniting surrounding materials. Modern LED downlighters run cooler but still often require specific installation methods or fire-rated housings. Finally, all outdoor light fittings must have the correct Ingress Protection (IP) rating (e.g., IP65 for weatherproof fittings) to keep moisture and dust out.

Preventive Remedies:

• Check that all metal light fittings, including those in the ceiling, are properly earthed.

• When installing downlighters, use fire-rated versions or install proper hoods/guards to create a safe clearance from insulation and timber.

• Verify that all outdoor fittings are specifically designed and rated for exterior use.

The Unseen Dangers: Illegal and Dangerous DIY Connections

Many CoC rejections stem from well-intentioned but hazardous DIY electrical work. These "handyman specials" often violate the most basic principles of electrical safety.

One of the most common illegal practices is the "fairy light" connection: spurring off an existing circuit inside the house with a length of thin, flexible "flex" cable to power an outside room, wendy house, or garden feature. This cable is not designed for fixed installations, offers no mechanical protection, and is a severe shock and fire risk. Another lethal practice is bypassing the earth leakage unit or a circuit breaker because it "keeps tripping." The tripping is a symptom of a fault; bypassing the protection is like disconnecting your car's brakes because the warning light is on. Finally, any addition of new plug points or light circuits without a permit and without the work being performed and certified by a qualified electrician is an unapproved addition that will void any chance of a CoC.

Preventive Remedies:

• Hire a Registered Electrician. This is the only surefire solution. For any electrical work, no matter how small, use a qualified professional.

• Be extremely wary of "handymen" offering cheap electrical work; they are often not qualified and their work is unlikely to be compliant.

• If a breaker or earth leakage unit trips, see it as a warning. Invest in finding and fixing the root cause, never in bypassing the safety device.

Your Pre-Inspection Checklist: How to Avoid Last-Minute Panic

To bring it all together, here is a practical, actionable checklist you can use to assess your property before calling an inspector. This won't replace a professional assessment, but it will help you identify and fix the obvious issues.

• Visual Check: Conduct a walk-through of the entire property. Look for cracked sockets, loose light switches, and damaged light fittings. Replace them.

• Earth Leakage Test: Go to your DB and press the TEST button. Does it trip decisively, cutting the power? If not, you need an electrician.

• Plug Tester: Use a cheap plug tester (under R100 at most hardware stores) to check for wiring faults like reversed polarity in every socket.

• DB Check: Open your DB (carefully!). Are all the breakers clearly and permanently labelled? Is the wiring inside neat, or a bird's nest? If it's messy, you likely need a DB upgrade.

• The Final & Most Important Step: "The single most effective action you can take is to hire a reputable, qualified electrician to conduct a pre-compliance inspection. This will identify all issues—both obvious and hidden—before the official CoC inspection, giving you a clear and cost-effective roadmap to full compliance."

Conclusion

Achieving a Certificate of Compliance is a rigorous process, but it is rooted in one simple principle: safety. As we've seen, a CoC rejection is almost always due to preventable issues related to safety, documentation, and adherence to the SANS 10142-1 standard. While the path to compliance may require an investment of time and money, this cost pales in comparison to the devastating consequences of an electrical fire or electrocution, not to mention the financial loss of a failed property transaction. Don't wait until you are forced to act. Be proactive about your property's electrical health. Always use a registered electrician—you can verify their status with the Department of Employment and Labour—and leverage the checklist provided. By taking these steps, you can secure not just your Certificate of Compliance, but also your peace of mind, knowing your property is a safe and legally sound environment.