Translated literally, une usine à gaz means a gas plant or factory.
What does this have to do with France’s Covid-19 health passes?
“We’ve been working on putting it [health pass rule] in place for months,” Dr Philippe Juvin, head of an A&E department in Paris, told France Info. “In a hospital, there isn’t just one entrance but many. And there are so many people who come in: police, firemen, ambulance drivers, maintenance workers, cleaners, kitchen staff.”
“Like many of my colleagues, I’m confused about how to apply the rules. We can see it’s a real usine à gaz.”
This expression dates to the French industrial revolution in the 19th century. During this period in France, gas factories started being built in industrial zones.
Typically they were composed of complicated systems of pipelines and crank handles that were incredibly difficult to understand.
Hence the use of une usine à gaz to describe any incomprehensible system.
More specifically it can be used to criticise a system that is big, expensive and complicated, but ultimately does not serve much purpose.
In this case, Dr Juvin was referring to the requirement to show a health pass in a new list of places, including hospitals (in non-emergency situations), from Monday, August 9.