Morning

In the OHS act it stipulates, " Any person who undertakes to do electrical installation work shall ensure that a valid certificate of compliance is issued for that work".

There is your answer in short.

The customer needs to be informed of this as the cost may change with this in mind i.e: you are asked to install a geyser timer and find the geyser not to be on an earth leakage.

Another important aspect is that the installation you are working on needs to have an initial COC as you can only issue a supplementary COC on the back of this or else you need to do a COC for the whole installation.