Colleague of mine at Glacto Smut Klim, had a ticket in a building, went in, front desk unattended, so went & put all his clean room kit on & went in search of the PC with the issue when came forth a very loud.
"What the fuck are you doing here?"
"Investigating a issue with this PC & keyboard, Why?"
I'm on the final walk through to check the building is empty, we are going to start fumigating it in the next 4 mins, didn't you see the signs at the front!"
"What signs?"
Indeed there was a complete lack of signage as all the regular staff were away, having been told it's a shutdown day & was deemed to be not required as the only people supposed to be there were the gassing team!