I am due to have a gas smart meter fitted soon. The chap I spoke to at British Gas was keen to make sure that I understood they would need to switch off my electricity supply for up to two hours. I'm just wondering why. I did ask him but he was a bit vague (not sure he really knew the technicalities) so could someone here advise. I'm assuming that BG meter switchers are fully competent with house electrics. I get my electricity supply from a different supplier.