11 common pools and spa work questions answered
Working around pools and spas is complicated. Questions about what the Standards say and how to follow them are some of the most common the MEA Technical team has to answer.
After a recent industry webinar on the topic, MEA’s General Manager Field Services Colin Gibson answered 11 of the most common questions about working around pools and spas.
Q. Should we be using jumpers on black metal fencing between posts and panels?
A. The Standard only requires the point of termination to the conductive structure and the earthing system of the installation. Therefore, we don’t have to check that the 0.5 ohm.
Q. Do we need to verify the bonding after concrete pour? Should we have two bond points on reo to verify after pour?
A. There is no requirement to verify by another testing means to ensure the single bonding point is sufficient to affect the entire grid of the reo. Clause 5.6.2.6.2 note 2 points out that we are relying on the tie wires installed by the contractor to provide electrical continuity. It the best solution we have without going to an alternative system such as spot welding every separate reo sheet together.
Q. Can the 4mm earth bond be connected to a 2.5mm power circuit earth or must the 4mm conductor be continuous back to the switchboard?
A. Refer to Clause 5.6.2.6 swimming and spa pools and 5.6.2.6.1 bonding arrangement. An equipotential bonding conductor, in accordance with Clause 5.6.3, shall be connected between:
(a) the conductive pool structure and the pool equipotential bonding conductor connection point specified in Clauses 5.6.2.6.2 and 5.6.2.6.3;
(b) the items of electrical equipment specified in Clause 5.6.2.6.4;
(c) the conductive fixtures and fittings specified in Clause 5.6.2.6.5; and
(d) the earthing conductors associated with each circuit supplying the pool or spa, or the earthing bar at the switchboard at which the circuits originate. Yes, either method can be used.
Q. What are fibre inground pools with metal tie down straps bonding requirements?
A. As the water container is insulated electrically from the ground, then any associated metal work that can be contacted by a bather would need to be bonded. The difficult aspect is where we have a metal shell that contains a plastic (PVC) liner would seem be insulated from the ground but could if punctured, now create a risk. In these cases, we recommend bonding the shell and any supporting conductive members.
Q. Does aluminium fencing mounted on non-earthed concrete need to be earthed?
A. Clause 5.6.2.6.5 conductive fixtures and fittings: Where any items specified in Clauses 5.6.2.6.2 or 5.6.2.6.4 are required to be equipotentially bonded, the bonding shall be extended to any fixed conductive material (such as pool ladders, diving boards, conductive fences, pipework and reinforcing metal in a concrete slab) that is installed within arm’s reach of the pool edge, and that is in contact with the general mass of earth either directly or indirectly.
Q. In relation to next door property being within the zone areas with an under 1.8m fence dividing the property. Does this affect the zone? i.e switchboard next door is within 2m of the proposed pool.
A. As this is a separate installation, it would be difficult to be able to control the environment of a neighbour. The switchboard requirement is for the safety of the user.
The argument would be that the neighbours pool would not pose a problem because the switchboard is not reasonably accessible by the owner of the pool. We would leave this to the state regulator to fathom.
Q. The Standard talks about a metal object that is in direct or indirect contact with the general mass of earth needs to be earthed. Can you please explain what this means?
A. The Standard does not mention “metal” but anything that is electrically conductive. The general mass of earth is a term which defines where the MEN system uses the ground to form a conductive area that has a direct reference to the generating source. For example, a steel pole inserted into soil would be class as in direct contact. A steel pole fixed to concrete that is in direct contact with the soil would be defined as indirect contact.
Q. Can a connection to the rebar in concrete be done with an earth stake clamp?
A. Not unless the clamp and reo was effectively connected together to form an electrical termination. A grey area which is always resolved by using a product specifically designed to be used on the correct size of the reo bar.
Q. When attending a site to wire a pool and the bounding earth is installed by others and encased in concrete, who is responsible if found to be not connected properly? Can we connect and highlight that the bond was installed by others?
A. The person who energises and puts into service the pool supply is also responsible for the bonding. If the electrical contractor does not have evidence (COT COES) of another licensed professional performing the bonding to the WR, then the responsibility falls on the electrical contractor.
Q. Do the regulations for pools and spas also apply to aquaculture tanks (10,000L) and large seawater aquaria for fish? Is there a guide as to IP rating of equipment and installation requirements of equipment (pumps, lighting, and immersion heaters)?
A. This only applies to a body of water that is expressly used for human bathing. Clause 6.3 sets the definition of swimming pools, spas.
Q. Do any of the bonding points need to be accessible, in particular the reinforcing on the pool which is mostly underground and the reinforcing mesh in the surrounding concrete paving?
A. There is no requirement for the bonding termination to be accessible for future testing purposes, but we need to test at the time we are terminating to confirm a low resistance reading. At the completion of the bonding, we would assume the termination is correct and subsequently test from the closest point to the termination to the bonding conductor connection point adjacent to the pool.
Do you have more questions about working around pools and spas? Master Electricians have unlimited, direct access to the MEA Technical Hotline. Speak direct to the experts, phone 1300 889 198.
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