Extraneous conductive parts

[Ian1981]

Hi all.
Looking for opinions on here.
I’ve identified during an eicr that a dry rise pipe used for firefighters in the building is in fact an extraneous conductive part and that it is not bonded back to the MET.
However what I’m questioning is it’s accessability to be touched in the event of a fault.
Pipework is installed in boxing with a key for an access panel for the riser water inlet to be used for the firefighters.
Only person with access is the building manager.
What’s people’s opinions does it require protective bonding or is it deemed not accessible to touch and that’s the end of the matter?
It’s worth pointing out bs 7671 doesn’t mention the fact it needs to be accessible however it’s common sense that says it needs to be if your going to be in contact during a fault between say an exposed conductive part and said pipework.
Thanks

To add the dry riser pipe comes up from the floor in metal and is separate from the cold water pipe entering the building in plastic.
A completely different service it seems.

 

[westward10]

Don't be put off you are a forum member who knows his eggs.

 

[Deleted member 26818]

Be useful if he explained himself better.

 

[Pete999]

No I just wanted you to explain your statement, it seems we are getting mixed up here Spin, of course I know the reason, it was just I thought your statement was a bit far reaching. And why you feel the vids are misinforming people that's all.

What do you think Spin?

 

[Deleted member 26818]

I would be surprised if the vids are mis-informing people.
Was concerned that you appeared to be unaware that Main Equipotential Bonding relates to extraneous-conductive parts.

 

[Pete999]

I would be surprised if the vids are mis-informing people.
Was concerned that you appeared to be unaware that Main Equipotential Bonding relates to extraneous-conductive parts.

Not unaware at all Mate, maybe a wrongly worded question.

 

[DPG]

I'm sure Pete knows full well what it refers to.

 

[Deleted member 26818]

You said this:

That is for main Equipotential bonding the OP is on about extraneous two different Animals, please see the vids I have posted.

If the vids are telling you that Main Equipotential Bonding and bonding of extraneous-conductive parts are two different animals, they are mis-informing you.

 

[Pete999]

You said this:

If the vids are telling you that Main Equipotential Bonding and bonding of extraneous-conductive parts are two different animals, they are mis-informing you.

I don;t think the vids are saying that, I think what caused the confusion especially in JW's Vid is that the different Animal, comes from the description of the differences of exposed conductive parts ie part of an electrical installation that is NOT normally live, electric metal heater framework , and an Extraneous conductive part, as in water,gas, oil pipework etc that doesn't form part of the electrical installation.

 

[Deleted member 26818]

As far as I am aware, the OP was referring to a dry riser, which would not be part of the electrical installation.
The OP started off stating there was an IR of 0.00 Mohms between the riser and the MET and that there was no continuity between the riser and a known earth.

I stated that 0.05 ohms is the maximum resistance for parts bonded to the MET.
In the OP’s case, I would use a low ohm meter to determine whether the IR reading of 0.00 Mohms is below 0.05 ohms.

 

[DPG]

Is this the 5 minute argument or the 10?

 

[Deleted member 26818]

Is this the 5 minute argument or the 10?

Getting a little ----ed off that people are disagreeing with me, then either posting vids or replying with posts that say the same thing I have said.

 

[Marvo]

Thread closed for a one hour cooling off period.

Deep breaths everyone, in through the nose, out through the mouth.

We'll be back shortly and in the meantime here's some soothing music.

 

[Marvo]

Thread reopened early because I'm off to bed.

By the way, did anyone notice the Pink Floyd song they sneakily slipped into that Muzak track?

 

[AJshep]

By saying no continuity do you mean low ohms measurement between MET and riser is off the scale (Im guessing greater than 200 ohms)

But insulation resistance between MET and riser is 0.00 Mohms.

Is that right? otherwise the information contradicts itself because no continuity wouldnt give a reading of 0.00 Mohms and maybe where the confusions is.

 

[Richard Burns]

The key point of the original question I think is is there an exposed conductive part, a live part (even if covered), or another bonded extraneous conductive part within 2.5 m of the hatch giving access to the riser.
The majority of the riser is inaccessible and therefore cannot introduce a potential; if the access hatch is not near any conductive part that may become live and can be simultaneously touched by a person or livestock, then the part at the hatch will also not be able to introduce its potential into the installation and bonding would not be necessary.

I think what Ian1981 is saying about measurements is as described in the below diagram. The riser is connected to true earth, but not connected to the installation protective conductors.