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My situation is I have been asked to install some equipotential bonds between pipes that carry explosive dust. The inside of the pipes is Z20. Outside the pipes is unzoned. The incoming pipe gets swapped between 2 different outgoing options via a flexible coupling so th the two equipotential bonds extended from the same location on the incoming pipe, across the break in the metal pipes to each section of outgoing pipe.

I'm just curious if I need to provide a CoC just for the installation of the earths?

Is it general or high risk prescribed electrical work, I would say yes so COC required

I'm not really sure to be honest. They aren't inside any zone but I guess they are directly associated with the hazardous area. Thanks Greg, I'm currently looking into this myself but just wanted to external opinions.

6A of the ESR's set out what is High risk, what is low risk and go on to say anything in between is General Risk.
The work in question is not low risk, and would seem to not be high risk - So then it is general risk, regardless of haz. area it's installation of new conductors. If I was doing the work, a COC would be in order

I agree; CoC is required for all installation of conductors that counts as PEW.
In defining installation of conductors as PEW; Schedule 1 does not restrict it in any way (eg to only current-carrying conductors).

Risk category is not so clear.
ESR 60(1)(b) requires electrical (part-) installation "in" a hazardous area to comply with 6079.14; and that's why the bonding is being done.
And ESR 6A classifies installation work "in" a hazardous area as high risk.
On a fine technicality, this specific installation work is not actually "in" a hazardous area; so could be certified as general PEW.
But it's only being done because hazardous area rules call for it; so it's directly associated with a hazardous area even though not technically "in" it.
The component parts of the bonding will need to be included into the verification dossier for the hazardous area;
just like all other hazardous area components.
So I can't think of any good reason not to treat this as high-risk PEW.

Paying for an inspection is much cheaper than wishing you had when the Board takes a different view of the work classification.
And it gives you in independent conformation that you've done it correctly.

Appreciate the input and opinions, I agree, rather play it safe than not

JamieP,
What sort of explosive dust are we talking here?
Is this some sort of an extraction system?
Also, what sort of length of run are we talking?

Cheers,
Mike T.

I'm not 100% sure what it was but it was infeed ingredients for making mozz cheese

Run lengths varied from 500mm to maybe 2000mm