To answer Brett's questions - firstly, fixed extinguisher installations. I have a D-type replica that has such a system. It's quite old and is filled with BCF (a halogenated hydrocarbon - now banned because it is a greenhouse gas). If the fire is detected fast enough and the system used in the first few seconds, I reckon it would be good. The main attraction is that you don't have to open the bonnet to apply the stuff (so it's quick and you are not allowing a whole load of air to enter). Nowadays I anticipate that a fixed installation will use something like AFFF - which is good but not in the same league as BCF, which is effective in small quantities because of the manner in which it extinguishes fire. The problem is that unless you have automatic detection, the driver starts to see smoke - or is that steam? Wastes a few seconds thinking about it, them decides to open the bonnet and take a look just to see, then realises there's a major fire brewing, panics, then remembers the extinguisher system - but how the hell does that pin come out of the actuator, panic some more, oh gosh, it's too late................... You need to be really well drilled to respond fast enough. So, overall, probably gives a nice feeling of security that will probably not be effective because it probably won't be actuated fast enough. Even with automatic detection things can go wrong. A detector cable works by having two conductors intertwined in the same cable - one is powered and the other earthed. Once a fire starts there is a short circuit between the two that sets off the extinuishers - foolproof? No, only last week I was asked to investigate why such a sysyem failed to work on a large landfill bulldozer that caught fire. I spent two hours figuring out how the system worked, finally followed the detector wiring to find the terminal had come of the vehicle battery....Ho Hum.
To answer you second question, I'm in Presteigne, which no one has ever heard of. It is east of Offa's Dyke, so it's not real Wales, but is over the Powys border, so we get the benefit of cheap Welsh council tax and free prescriptions. Alas, we are putting the house on the market today with a view to move south - back to 'civilisation'.
Cheers
