It was all too easy to accidently leave a gas tap open. For instance, most of us urban wrinkles lived with town gas supplied through a coin-in-the-slot meters and often the gas would start to "run out" and it was a race to get another shilling in the meter before the flame died. Then, after inserting a shilling all that's needed is a distraction and the gas is flowing.
Add some alcohol to the equation and you have all that's needed for a tragedy.
My mum used to like it when the gasman came to empty the money. We always got a welcome rebate.
