Electrical Hazards with Plumbing
Most of us know to always use qualified electricians for any electrical work in our home or workplace, but don’t realise there can also be serious electrical risks associated with plumbing tasks.
So how does plumbing work create electrical risks?
Most homes and buildings have electrical earth wires connected to water pipes. This is done as a safety feature to ensure any inadvertent electrical connection or stray electrical current is safely carried to earth.
However, if the necessary safety precautions are not taken before carrying out plumbing work, people may be exposed to stray electrical current in water pipes or associated fittings, like; sinks, dish and clothes washing machines, “InSinkErator”, or evaporative air conditioners.
Note that even the simple task of cutting a water pipe and cause an electric shock.
But we have an Electrical Safety Switch!
Increasingly, houses and workplaces are (correctly) being protected with earth leakage/ residual current devices (RCD), commonly labelled in switchboards as safety switches. However, most people do not test these devices periodically as recommended by the manufacturers making it unreliable.
Key precautions for plumbing work
Professional plumbers will have detailed training on this subject, but the essential precautions include:
a) Turn off the power at the main isolator switch and attach a ‘Danger – Do Not Use’ tag and lock if possible.
b) If power is required, don’t rely solely on switchboard safety switch, but use a power board with built-in safety switch for portable power tools.
c) Ensure all electrical leads are correctly insulated to minimise risk of metal roofs, gutters and pipes becoming live.
d) Check metal roofs, gutters and water pipes with a volt meter before work to ensure they are not live. If the voltage exceeds 5V, do not proceed, call an electrician.
e) Connect bonding/bridging clamps across the section of water pipe to be cut. Do not work outside of the bridging clamps.
f) Connect bonding clamps (>70amps capacity) to main earth if connection needs to be disconnected at any time.
g) If plastic water pipes or fittings are to be installed, engage an electrician to ensure all plumbing sections remain correctly earthed.
Resources for Electrical and Plumbing Safety
References and additional safety resources on this topic include:
1) Electrical Safety for Plumbers – Fact Sheet, Endeavor Energy.
2) Plumbing Newsflash – Electrical Safety for Plumbers, Queensland Government, 1 Dec 2016.
3) Australian Standard AS 3500 Plumbing Glossary.
4) Code of Practice – Working Near Exposed Live Parts, Qld Government, 2002.
Gary Rowe, CEO
Safety Action Pty Ltd