Toasters - The scourge of the workplace.
Someone in our office once attempted to make cheese on toast by turning the toaster on it's side. Yes, really.......
Discounting the various hideous hygiene issues of this, the user then left a toaster unattended to go the loo. The resulting smoky conflagration resulting in a full evac of a 600+ staff for 45 minutes until Barney McGrew and co could turn up to pump out the smoke and confirm that this man was, indeed, an idiot of the highest order.
Why 45 minutes? Well that's simple, the fire alarm company had been in to service the system a few days prior and diverted the callout line to their head office for testing, instead of the Fire Brigade. They then forgot to swap it back afterwards.... So at least the incident flagged up that little treat up without anyone being hurt.
The staff member involved is now no longer allowed in the kitchen