Bonding suspsended ceiling grid

[Stroppy]

Do you neeed to bond a metal suspended ceiling grid when it will be covered with plasterboard?

My colleague says no, as it is inaccessible (unlike if it was removable ceiling tiles), and therefore not an extraneous conductive part, but I say it should be bonded as it has cables running through it which may be prone to damage by plasterboard fixers, potentially livening up the grid. Even if you don't have to, I would think it would be 'best practice' to bond it, as the nearest part of it to the MET is probably less than a metre away.

 

[telectrix]

your colleague is right. it's not extraneous so you don't bond it.

 

[Stroppy]

Thanks, good to have a second opinion. My colleague has stated serveral things as gospel truth which turn out to be codswallop, so though I'd better check!

 

[MDJ]

yes that was 15th edition stuff and no longer a requirement, we are harmonised with europe now and can run flexies through flowerbeds in restaurants without protection, bring on the 18th.

 

[Deleted member 26818]

It wouldn't be bonded as an extraneous-conductive-part, however it could be earthed as an exposed-conductive-part.
I have heard, although it might be an Urban Myth, that an Apprentice incorrectly wired a light fitting, and when the Electrician climbed the ladder to sort it out, the Electrician got a belt.
The Apprentice had some how swopped the line and earth conductors when terminating.

 

[telectrix]

can't see it as being an exposed conductive part of the installation unless cables are routed through the metalwork of the grid.

 

[Geoffsd]

My colleague says no, as it is inaccessible (unlike if it was removable ceiling tiles), and therefore not an extraneous conductive part,

It doesn't need bonding. It's not extraneous.
Nothing to do with being covered or not

but I say it should be bonded as it has cables running through it which may be prone to damage by plasterboard fixers,
potentially livening up the grid.

you think that is likely, then that would be earthing.

Even if you don't have to, I would think it would be 'best practice' to bond it, as the nearest part of it to the MET is probably less than a metre away.

We don't bond or earth parts because it's nearby.

It's done to ensure safety from the likeliest hazards.

 

[Deleted member 26818]

can't see it as being an exposed conductive part of the installation unless cables are routed through the metalwork of the grid.

The grid supports the light fittings and often the cbles to the fittings.
As such I would consider it to be a form of containment.

 

[SYKRAPS]

I can't say that I have ever seen a ceiling grid evre being earthed for a suspended ceiling never mind a concealed suppoert system, imagine all of the bonding links that you would require to bond each and every separate strip of ceiling grid, there would be 10 x more work required doing that than the connection of the lighting and sockets etc.

However I have seen countless numbers of times where cables are just sat on top of a ceiling grid where the installation and addition are put in place by lazy t**ts...................and when you remove a tile the lot falls on your head. Rant over :dots:

 

[MDJ]

in the eighties we always earthed the grids lol, it was the done thing back then, a 6mm2 earth wire slung over the ceiling and bolted via yellow lugs and 4mm2 nuts and bolts through the main tee bars, looking back at it now it is quite laughable haha

 

[Stroppy]

can't see it as being an exposed conductive part of the installation unless cables are routed through the metalwork of the grid.

Ah now you come to mention it, some cables do pass through parts of the grid (via grommets, of course!) on their way down through wooden studs to light switches, sockets, etc. Every single cable in the flat is clipped to, lays on, or runs through this ceiling grid, which made me think earthing it would be sensible.

We don't bond or earth parts because it's nearby.

True, what I meant was if something big and metal technically doesn't need bonding according to the regs, but is easily done, then why not? Maybe I'm being too thorough.

 

[Geoffsd]

True, what I meant was if something technically doesn't need bonding according to the regs, but is easily done, then why not? Maybe I'm being too thorough.

Because then you would be creating a hazard which was not there before.

Parts which do not require bonding should not be bonded.

 

[ayjay]

i think its a good thing to earth any metal ceiling grid

 

[Stroppy]

I always remember the tale a former colleague told me about a job he went to in a school to change some fluorescent light panels, where some numpty had left a live bare cable above and touching the ceiling grid making it live. He pushed out a tile and touched the grid and got a bad shock through his hand, and on recoiling from that hit his neck on the part behind him and got another shock, then twisted his ankle falling off his step ladder. Had the grid been earthed....

 

[DPG]

Imagine how many nuts and bolts, and lengths of cable you'd need to connect all the seperate pieces of grid together. Jeez, it'd take you all week! Daz