1972 ..... back when they had gas lamps and naked flames..When men were men.. really!
We are talking about earlier today when if your trading premises are not inspected, licensed and certified to trade. You will be dragged straight to court and sued should you cause harm to any customer through negligence. Keeping a property open in a power cut would be deemed negligent. Slips, trips, spills, alarms, sensors, lighting, ovens, pumps, think about it. Health and safety has been put in place for a reason.