Kzzzzrrrrt
Workplace chum of mine had a previous existence working with some shopfitters. On one job hie had been tasked to drill a hole into the bottom of the display window, carefully avoiding the 440V 3 phase cable underneath which was very clearly shown on the authoritative site drawings.
Unfortunately the site drawings didn't actually
reflect reality.
Apparently he was still smoking as he was stretchered to the ambulance.