Bonding metallic pipework

[MDJ]

therefore thats why I have not done it.

You won't get repeat business from this consultancy if you attempt to argue with the electrical engineer who designed the job and wrote the specification, unless it is a dangerous situation get on and do it, and smile whilst carrying out the work as well, at this level any trouble you cause will not be forgotten, and IME a lot of engineers are buddies and play golf together, if word gets around you are difficult you may not get much future work at all, get on with it man!!!

 

[telectrix]

it's a bit like an alarm company i worked for once. if the "consultant" specifies a magnetic contact on the karzi lid, then he gets a magnetic contact on the karzi lid.

 

[Engineer54]

I get the impression that the OP doesn't have much experience with Spec'd job's/projects!! As i stated before the specification forms a large part of the contract, as well as will contract procedures. Any quotation price submitted to win a contract, should be based very much on the specification required. So the cost of materials and man hours associated with particular items of work, will be taken as covered by the winning contractor to the client. Start omitting work, or disregarding specifications and your well and truly in breach of contract. Penalties can be crippling under the umbrella of contractual law. Stating minimum BS7671 requirements, or any other recognised code /reg or BS wouldn't be entertained as a defence, unless it can be proved the contract/specification was in contradiction/compromised that standard!!

Thing's can and often do get changed within specifications during the course of the contract, but only via following the contracts laid down procedures. ALL changes will be in writing and agreed between both parties, BEFORE such changes are incorporated into the work. But remember any changes will have a cost implication one way or the other!! lol!!

 

[PRR]

> a connection is made for every 230m2 of floor area

So if the facility is 230m long, and a conduit runs crossways, it has to be bonded every meter?

Area-based sure is odd. If the goal were RF interception, area is part of it, but also length of run. If the goal is to limit step-touch fall-of-potential shock hazard from some large electric source to remote earth, then the critical measure is distance in direction of that source. In extreme cases you would grid the whole lot, floor, even grid the walls (metal walls are pretty extreme, but I have seen rooms enclosed in tight mesh.) Also all suspended-ceiling metal, all metal water pipe, metal door-frames......

If the job is that earth-happy, then even if you aren't asked to do the walls pipes doors, you should be prepared to accept their bonds in your earth-bus. (See spinlondon's massive earth-bar.)

> Its a care home

So, old/sick people? Extra caution is warranted.

It WOULD be distressing if somebody died and your name came up in the investigation.

I'd do all the joints extra good, AND do an explicit bond every 50 feet (which is what 230m2 seems to imply). What the heck, it is THEIR contract and thus their money. Extra work for a quasi-reasonable reason and clearly specified in contract is just extra money for you.

 

[snowhead]

> a connection is made for every 230m2 of floor area

So if the facility is 230m long, and a conduit runs crossways, it has to be bonded every meter?

NO, there's no care home in this country that's 230mtrs long.

Bonding is every 230m2, so every area 23 x 10 needs 1 bond.

The home my Mother is in is made up rooms 5 x 4 mtrs either side of corridors 3mtrs wide.
So each opposite pair of rooms and section of corridor = 52mtr2.
That's bonding approx every 9 rooms.
In a 60 bed home with several lounges and dining rooms that would probably be a dozen bonds.

 

[Stroppy]

The first post only mentions pipework, and as it is square metres specified it shouldn't be too arduous. Errr as Snowhead has pointed out. The designer is probably anticipating plumbers hacking the installation about and putting plastic connections here there and everywhere, and is trying to maintain effective bonding. You'd only have to bond every metre if the home was only 1 metre wide!