used to work for a company that supplied trace heating for process/chemical/water purposes (B****C) - wasnt my department as such but i could probably resurface the brain cells that dealt with it!! - it wasnt cheap - even the domestic range we sold to keep water pipes up to temp etc - the self regulating stuff was good s**t though - they used to supply it to keep airbus wing controls from freezing up - it had to be certified to be up to the job (tbh it was the same stuff as the general industrial stuff but you got a 80 page certificate and paid 3x the price!!!!)
atb
chris
**slight mod to word, V**