All the exposed metal with the exception of the centre trim plate is earthed on the Australian version of that iron, and that part is separated from the rest of the metal by the Bakelite of the handle. He shouldn't have got a belt unless there was a fault in the extension lead, or there was enough condensation or spilt water inside the iron to conduct current from the live terminal inside the handle to the trim plate. Maybe it was filled sloppily. I've not heard that these irons were dangerous. My Mum used an FS17 for years without trouble. The type was still in production as the Black & Decker Classic well into the 21st Century.
