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Tell you what though, I’d be with you when it comes to major storage magazines. I’ve just watched a video from Beirut today. That was one astounding bang, the shockwave created its own meteorological effect. I reckon that was tens, if not hundreds of tonnes of HE, all going off at once. Not ideal.
Sad to see, as if Beirut has not suffered enough already :(
 
UPDATE
For anyone who might be interested in this thread in the future, I'll document my 'As Built' progress. I've finished most of the structural and plumbing stuff now so am installing the electrics.

I gave up all thoughts of dedicated dado power strip, and went with a run of 50 x 100 Salamandre galvanised trunking (From CEF, £7/m).

This meant cutting the lid manually, but avoids the multiple lid joints in the commercial systems. Inserting MK panel mounting plates, in what I think is the wrong place, ie behind the panel (lid), works well and will allow completely flush installation of accessories.

Advice on designing an electrostatic-proof building please. DSC_1347.JPG - EletriciansForums.net

Also for wiring you would be looking at stuff in metal trunking ... or far simpler to handle using Flexishield cable ...

Thanks for the tip. I hadn't used Flexishield before and it's brilliant stuff. As is the recommended RS 262-0151 circular cable stripper. It makes T&E feel a bit Neanderthal :)

It sits nicely in the trunking, and stays where you put it.

Advice on designing an electrostatic-proof building please. DSC_1350.JPG - EletriciansForums.net

As I can't use compartmented trunking as it would foul the accessories, I'm sleeving the ELV stuff: alarm, dc power supply, data, etc with braid, then tying it off at the top of the trunking. As this in non-standard, I'm not entirely sure if this satisfies current separation requirements but can't see why it's not OK electrically.

The picture below shows one dc power point, none of which will be close to any mains accessory.

The yellow socket is one of what will be multiple points at which to plug in (resistored) ESD wrist bands, or to ground items of portable lab apparatus.

Advice on designing an electrostatic-proof building please. DSC_1351.JPG - EletriciansForums.net

To be continued :)
[automerge]1598748353[/automerge]
Three types of Hazardous Areas are recognised as follows:
...

• Explosives Hazardous Areas – An area in which explosives material/substances of Explosives Ordnance are exposed to the atmosphere such that they require special precautions for the construction and use of equipment in order to prevent ignition of an explosives material/substance.

sound suspiciously like the material your working with... These rules don’t just apply to the Oil & Gas and offshore industries mate.

I researched these regs, of which I knew nothing, in detail.

As I suspected it's all about explosive atmospheres - eg gas/air, solvent vapours, flammable dusts - not Class 1 explosive materials sitting on a bench.

The statement '... An area in which explosives [sic] material/substances of Explosives Ordnance are exposed to the atmosphere' does not mean the general atmosphere of the Earth, it means any explosive atmosphere to which the ATEX regs apply.

But it's unclear why anyone would want or need to break open items of explosive ordnance while surrounded by an explosive atmosphere. It would be an extraordinarily reckless thing to do :)
 
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UPDATE
For anyone who might be interested in this thread in the future, I'll document my 'As Built' progress. I've finished most of the structural and plumbing stuff now so am installing the electrics.
Great to see an update! No matter what the matter or problem discussed, I think we all like to hear how it was resolved, etc.

I gave up all thoughts of dedicated dado power strip, and went with a run of 50 x 100 Salamandre galvanised trunking (From CEF, £7/m).

This meant cutting the lid manually, but avoids the multiple lid joints in the commercial systems. Inserting MK panel mounting plates, in what I think is the wrong place, ie behind the panel (lid), works well and will allow completely flush installation of accessories.
That looks like a good way to do things.

Thanks for the tip. I hadn't used Flexishield before and it's brilliant stuff. As is the recommended RS 262-0151 circular cable stripper. It makes T&E feel a bit Neanderthal
Yes, I'm a recent convert as well!

Also it shares the SWA attribute of being shielded in the electrical safety sense - so if punctured it will trip the MCB, etc, and disconnect safely. (OK in your case the resulting spark might not be good, but at least there is little electric shock risk).

As I can't use compartmented trunking as it would foul the accessories, I'm sleeving the ELV stuff: alarm, dc power supply, data, etc with braid, then tying it off at the top of the trunking. As this in non-standard, I'm not entirely sure if this satisfies current separation requirements but can't see why it's not OK electrically.
Off hand I don't know if there are very specific requirements for separation, but certainly having an adequate air gap under any realistic cable movement, and the presence of the braid (and shield on the Flexishield cable) would satisfy me.

Just one point, how are you earthing the added braid for the DC and signal cables?

The picture below shows one dc power point, none of which will be close to any mains accessory.
I guess they are all current-limited so low risk of any significant spark or even thin wire overheating if accidentally shorted out?
 
As per the above post, you need to look at the configuration of the braid and insulation of the ELV stuff in the areas around mains accessories where only basic insulation is present.

Consider a broken / faulty mains socket that exposes some live component to the interior of the trunking; unlikely but I've seen a line terminal break out of the back when the socket was hit at the front. If that component contacts the exposed braid, will it reliably witshtand the fault current in the way that the trunking would? Will it blow through and allow contact with the ELV circuit? I would rather have seen it insulated, perhaps by running plastic mini-trunking along the back of the steel trunking.
 
One aspect I mentioned earlier was the issue of fault energy and trying to keep it to a practical minimum by choice of MCB / backup-fuse / etc. That would also help a bit with the braid fault ratings.

Also worth asking if there are any plans for emergency lighting if power should fail? You would not want to knock some of those chemicals off the bench in the dark by mistake!
 
Why would you use flexshield inside trunking?

Where are the back boxes for the sockets?

It looks like the kind of thing that Diyers come up with in their sheds/garages, just on a neater/bigger scale.
 
The steel trunking that offers socket outlet plates like Legrand or Unitrunk don't provide back boxes either, so it is no different (just cheaper but more work).
 
The steel trunking that offers socket outlet plates like Legrand or Unitrunk don't provide back boxes either, so it is no different (just cheaper but more work).

No it isn't any different, the products you mention also aren't, in my opinion, suitable for use in trunking where there are ELV cables and terminals exposed.

Just because a manufacturer makes a product it does not automatically make its use safe and compliant in all situations, especially not non-standard situations.
 
This job is now done. Thanks for all the help and advice.

For anyone who was following, or may come across, this thread in the future here are the completion updates, 'as built.'

Someone asked how I earthed the braid. Solder and shrink fit:

Advice on designing an electrostatic-proof building please. DSC_1352s - EletriciansForums.net

Braid is used over any plastic plumbing to provide earth continuity to the ESD ground:

Advice on designing an electrostatic-proof building please. DSC_1361.JPG - EletriciansForums.net
For those interested in these things, the waste plumbing is in 'Vulcathene', which is acid-resistant and highly recommended.

There were comments on the non-desirability of having 13A sockets exposed behind the work benches, which may hold exposed hazardous materials. I don't believe this is really a problem, but I used floor sockets to keep them covered up when not in actual use:

Advice on designing an electrostatic-proof building please. DSC_1354.JPG - EletriciansForums.net


The DB installation is now finished. As this is potentially a portable building, it's fed from a 5 pin appliance inlet externally:

Advice on designing an electrostatic-proof building please. DSC_1438.JPG - EletriciansForums.net

The incoming device provides 30mA protection to the whole installation.

The two small relays top left are for security lighting (common to the whole site) which activate internal and external lighting in case of alarm activation.

The PSU on the shelf provides ELV lab power.

The 'greenhouse' thermostat controls a single oil-filled radiator, and can be left at 4C for frost protection.

As far as possible all internal fittings are metallic, and bonded together and to earth.

The walls are clad in painted aluminium sheet from Aalco, with stainless steel jointing strips.
 
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Nice to see the finished job!

I also have one of those frost thermostats lying around intended for controlling some self-regulating heating tape for frost protection of an external water pipe. But so far been too busy to fit it and suddenly it is winter again...
 

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