Lightning Protection

[Gibeltariq]

I have a seven storey office building built about 25 years ago in which an Ionisation lightning protection was installed. This consists of a radioactive material at the the top of the finial and a single down conductor through the atrium of the building. Several buildings here have this system fitted and I am suspicious about its efficacy and have a two questions:

1. Does this system in any comply with BS for the installation of lightning protection?

2. Is the British Standard for Lightning protection retrospective?

3. What do the insurance companies think of the system?


I have a meeting with the Landlord with this subject next week and I would like to see this 'Ionisation' system replaced with the latest BS standard and it will expensive. Has anyone got any convincing arguments for installing an up to date installation?

 

[Knobhead]

Radiation Protection Division of the Health Protection Agency are the ones to talk to first if there are any isotopes involved.

View attachment 8160

 

[Engineer54]

I have a seven storey office building built about 25 years ago in which an Ionisation lightning protection was installed. This consists of a radioactive material at the the top of the finial and a single down conductor through the atrium of the building. Several buildings here have this system fitted and I am suspicious about its efficacy and have a two questions:

1. Does this system in any comply with BS for the installation of lightning protection?

2. Is the British Standard for Lightning protection retrospective?

3. What do the insurance companies think of the system?


I have a meeting with the Landlord with this subject next week and I would like to see this 'Ionisation' system replaced with the latest BS standard and it will expensive. Has anyone got any convincing arguments for installing an up to date installation?

I've installed many of these ionisation LP systems over the years, there is absolutely nothing whatsoever wrong with them. They are more prevalent throughout the Far East where they are now considered the normal LP system and to a lesser extent the Middle East. Iv'e personally seen these systems working, and on far more than one occasion. Believe me, they have far more and far bigger/intense thunder storms in the the Far East than you will ever see in the UK. Look around on the internet to get the technical stuff on these systems/units, but you can actually design/manipulate the zone of protection by adjusting angles and direction on the side spikes.

These systems have been installed on some of the highest and the most prestigious buildings in Asia in preference to the use of conventional LP systems. They have only just started to gain approval in France and Germany because of fierce opposition from conventional manufacturers and suppliers with unfounded assumptions, as against proven recorded data. Obviously the conventional manufacturers will be losing out on supplying all that copper that is, the very basis of there systems. No idea if they now have a BS number or not, but someone must have approved there use on your building, and obviously the insurers of the building have had no objection to there use either!!!

Provided the ionisation unit(s) have been sized correctly and located correctly they will in all likelihood provide equal or better protection to any given building... They will in the future be replacing the conventional systems on new and old buildings...

 

[Knobhead]

Think I set off on the wrong foot here. Any reading on this you can recommend E54?

 

[Engineer54]

There is a huge amount of data on the internet on ESE Lightning Protection systems. The conventional companies like Fuse and others, are now being hit hard as the cost of conventional systems in terms of both materials and man hours to install is substantially more than an equivalent ESE protection. Also conventional systems become less effective the higher a building or structure is.

Anyway here's a study/report to read to get you started...

http://www.intlpa.org/pdf/efectiveness_worldwide_ese.pdf

 

[Gibeltariq]

Thank you all for responding to my request.

The British European Standard is BS EN 62305 4 parts and they are expensive to buy. As engineer 54 says, installations to this standard they use a large amount of copper and installation costs are expensive. I do not have access to a copy at this moment and I remember someone telling me that some of the 'Authors' are associated with the copper industry!

The discussion point on the lightning installation has changed since I last wrote and the client is concerned about the resistance of the earthing rods, a problem they had three years ago which resulted in a local contractor installing horizontal runs of 20m or more to flower beds, including an 'Up and over' a wall'! directly from the down conductor. I recall that may reduce the resistance, but not the impedance which is what a lightning strike sees.

So it seems I will go back to basics, bore a hole into the limestone, fill it with betonite and drive a rod into it, should be fun, as it is at the bottom of a lift shaft. The next problem is sorting out how to test it.

Thanks again.

 

[Engineer54]

The basic standard for these systems is 2 down conductors from the Air Conductor. These terminate at two crows foot earthing arrangements, again usually either side of the building. As you say, if you have a limestone rock formation under the soil 75 to 100mm dia bore holes filled with bentonite is the usual method. I would also mix in an amount of carbon powder to enhance the conductivity. There is nothing to stop you using more down conductors, if your experiencing difficulties bringing your RA values down.

Up and over a standard width wall is not a very good idea, as any lightning strike will be trying to jump the angles and can destroy the tape or cable. Far better to drill a hole thru the wall.

Boring or driving rods at the bottom of the lift shaft is a completely dozy idea, especially if you are bringing the down conductor down the lift shaft. The lightning strike will be flashing all round the shaft ....including the lift car itself, putting any occupants at very high risk. One of the reasons that lift shafts should not incorporate any other electrical system except those associated with the lift installation itself. That i am almost sure, is a statutory regulation, and one of the better one's too!!! DONT DO IT!!

 

[Gibeltariq]

Engineer54,

I totally agree with what you are saying, what is against me is that the installation has been as it is since 1986 and the client says 'What is wrong with it? it has been like it since it was built'. A phrase I have heard several times on other jobs.

I have had the lift engineer in to look at the lightning down conductors and he not say anything. The highest point of the building is the lift motor rooms so naturally the ESE conductor is on top of it with the down conductor following the shortest path down adjacent to the lifts with exposed cabins in an atrium.

If it aint broke, why mend it?

 

[Engineer54]

Engineer54,

I totally agree with what you are saying, what is against me is that the installation has been as it is since 1986 and the client says 'What is wrong with it? it has been like it since it was built'. A phrase I have heard several times on other jobs.

I have had the lift engineer in to look at the lightning down conductors and he not say anything. The highest point of the building is the lift motor rooms so naturally the ESE conductor is on top of it with the down conductor following the shortest path down adjacent to the lifts with exposed cabins in an atrium.

If it aint broke, why mend it?[/QUOTE]


If that down conductor is run in the lift shaft either walk away, or try one more time to convince the idiots that they are putting life's at risk breaking more than just one saftey regulation. It's been OK since 1986 won't wash in a court of law on manslaughter charges, that i Do Know!! lol!!

But it is Broke, ....That's why your there , if i'm not mistaken

 

[Gibeltariq]

I will take a photo of what I am dealing with and start thinking of an alternative route for the down conductor. Architects are a nightmare sometimes!

 

[Engineer54]

I will take a photo of what I am dealing with and start thinking of an alternative route for the down conductor. Architects are a nightmare sometimes!

Not when they can be held liable on breeches of H&S regulations there not ...lol!!!

Yes a photo or two would be much appreciated....

 

[Gibeltariq]

Engineer 54,

Attached is a photo of the lightning conductor we have been talking about. As they say. 'a picture is worth a thousand words'. The question is: is the down conductor within the lift shaft?

 

[Engineer54]

Becomes much clearer now Gibeltariq, not an actual lift shaft but still on the building fabric associated with the lifts, and in quite close proximity to the 2 working public lifts.

Personally, i think the proximity to these 2 lifts is just too close for comfort, and the steelwork associated with them could well provide a better path to earth than your down conductor, from what you have posted before. In fact i don't think i've ever seen a lightning down conductor routed through an interior public area let alone so close to lift equipment. Is that down conductor 50mm2 hard drawn copper, or normal soft copper??

I wouldn't be happy with this installation Gibeltariq, you can try and get another opinion, but i'm pretty sure your not going to find anyone that knows about lightning Protection, that would be too happy about this down conductor routing either...