About the specialist's EES.

Attract or prevent...which one will YOU choose?

There are three basic options in lightning protection today...

Attractive
Passive
Preventative

Attractive systems known as ESE's (early streamer emitters) claim to speed up the process of ionisation to such an extent that the ESE device saturates with ions earlier and is therefore able to cast a streamer further than a standard finnial.

This allows the downward leader to be intercepted and 'pulled' towards the building where the ESE is installed.

The rationale being "it's better the YOU deal with the problem than let it attach to something or somewhere else".

The upside to this option is that they are cheap to install. The downside is they are not accepted by British Standards and will attract a strike to your building/s.

Neutral/passive (BS6651 & BS EN 62305)

Based on the traditional designs of nearly 250 years and by far the most common of systems currently in use; neutral systems use the principles developed by Faraday and Franklin to deal safely with any incoming strike by distributing the lightning current via several parallel paths to ground.

The benefit of these systems is they are well understood and accepted by standards bodies all over the world, including British Standard's.

The drawback is that they can involve a large amount of tape to form the Faraday's cage...which might be a problem for a listed building (historical importance).

Detractive

The last option is known as CTS (charge transfer system). This has a strong foundation in physics and has a phenomenal track record. One might argue this is the ultimate in protection, as they get straight to the 'source' of the problem and neutralise the chance of a strike even being created!

The upside benefits are obvious...zero strikes, no worries. The downsides are harder to pin down other than they are currently the more expensive option.

more info...