Written by: Grant Seeman – National Technical Advisor
Wired to Comply: Understanding the Standard Test Report
A practical series on the four inspection questions and 15 tests in SANS 10142-1
Part 5: Test 1 – Continuity of bonding
The first test in Section 4 of the standard test report reads:
“Continuity of bonding – Compliant.”
This is the first actual test after the four inspection questions.
Bonding and earthing are closely related, but they are not the same thing. A bonding conductor connects exposed or extraneous conductive parts together to bring them to the same electrical potential. An earth continuity conductor, which we will deal with in the next article, provides the earth path back towards the installation earthing system and is intended to carry fault current.
Clause 6.13 explains that the aim of bonding is to bring the bonded parts to the same electrical potential. Clause 8.6.2 then tells us how the continuity of that bonding is confirmed.
Why is this important?
Imagine two metal parts close enough for a person to touch at the same time. If a fault causes one of them to rise to a dangerous voltage while the other remains at a different potential, the person touching both could become the path between them.
Bonding is intended to reduce this risk by keeping the relevant conductive parts at the same electrical potential.
Simply seeing a green/yellow conductor or a bonding clamp is therefore not enough. The connection must actually be electrically continuous.
What must be confirmed?
The registered person must establish that:
• The bonding required by the installation is present.
• The required conductive parts are effectively bonded together.
• Continuity exists between exposed conductive parts within arm’s reach of each other, where required.
• Where an instrument is used, it complies with the test requirements of Clause 8.6.2.
• The measured resistance does not exceed 0,2 Ω.
• Any bonding conductor that is installed is correctly sized and arranged so that it cannot easily be tampered with.
Clause 6.13.1 requires a bonding conductor to have a nominal cross-sectional area of at least 2,5 mm² copper or equivalent and to be arranged so that it cannot be tampered with.
The standard also makes an important point: a separate external bonding conductor is not automatically required if the necessary continuity can already be proved by the test in Clause 8.6.2. In other words, the important issue is the electrical continuity of the bonding path, not simply whether another piece of green/yellow conductor has been added.
How is the test carried out?
First identify the parts that are required to be bonded.
Depending on the installation, these can include conductive hot and cold water systems associated with electrical hot-water equipment, accessible extraneous conductive parts associated with water pumps, other conductive services entering the premises and, where the specific requirements apply, conductive roofs, gutters, downpipes and waste pipes.
For example, where an electric hot-water system has conductive water pipes, Clause 6.13.2.2 requires the hot and cold water systems to be bonded together and to the earth continuity conductor system.
Do not merely inspect the bonding clamps. Confirm the electrical continuity of the connection.
Clause 8.6.2 requires continuity to be confirmed between exposed conductive parts within arm’s reach of one another. Where a test device or instrument is used, its supply must have a no-load a.c. or d.c. voltage between 4 V and 24 V, and it must be capable of supplying at least 0,2 A.
The resistance must not exceed:
0,2 Ω
This is important. A normal continuity “beep” on a multimeter does not by itself tell you that the bonding complies with the 0,2 Ω requirement or that the instrument meets the test requirements specified by the standard.
Clause 8.6.1 also requires applicable results to be recorded where multiple tests are necessary and attached to the test report. The standard test report itself simply records this test as “Compliant”, but the registered person still needs the test results on which that conclusion is based.
Common mistakes
Common mistakes include:
• Looking at the bonding conductor and assuming it is continuous without testing it.
• Accepting a continuity buzzer without confirming the actual resistance.
• Using a test instrument that does not meet the requirements of Clause 8.6.2.
• Accepting a resistance above 0,2 Ω.
• Missing loose, corroded or poorly fitted bonding clamps.
• Testing from the distribution board earth terminal to the equipment and calling this the bonding test. That is the earth continuity test covered in Test 2.
• Adding a bonding conductor without first understanding what is actually required to be bonded.
What if the result is unacceptable?
A high resistance or open circuit must be investigated.
The problem could be a loose or corroded connection, an ineffective clamp, a broken conductor or an interruption in the conductive path being relied upon for bonding.
The defect must be corrected and the bonding retested.
Regulation 9(3) of the Electrical Installation Regulations requires the registered person to refuse to issue the Certificate of Compliance until a fault or defect detected before certification has been rectified.
Practical tip
Do not ask only:
“Is there a bonding wire?”
Ask:
“Are these conductive parts actually electrically connected together, and can I prove that the resistance between them does not exceed 0,2 Ω?”
Key takeaway
Bonding is about bringing conductive parts to the same electrical potential. The presence of a conductor or clamp does not prove that the bonding is effective. The continuity must be confirmed, and where it is measured in accordance with Clause 8.6.2, the resistance must not exceed 0,2 Ω.
Where this information comes from
This article is based on SANS 10142-1:2026 Edition 3.3, particularly the definition of a bonding conductor, Clauses 6.13, 8.6.1 and 8.6.2, and the standard test report. The requirement relating to issuing a Certificate of Compliance is taken from Regulation 9(3) of the Electrical Installation Regulations, 2009.
