Temperatures are soaring but Southeastern are telling parched punters not to drink water from their train toilet bowls this summer.
The company has become the butt of online jokes after traveller Tom Papworth spotted this sticker on the back of a toilet seat while travelling from Victoria to Orpington.
It helpfully warns confused commuters who might be tempted to guzzle straight from the can: "Not drinking water."
He tweeted: "Thank you, @Se_Railway for saving your passengers from a fate worse than death. #NotDrinkingWater"
It is not know how many, if any, travellers have mistaken their train's loos for a water fountain and taken a cool, refreshing drink.
A spokeswoman for Southeastern said: "I'm sure all of our passengers will have worked out for themselves that the water in this particular location isn't suitable for them to drink, but it never harms to state the obvious.
"We're reviewing the location and number of signs on our trains at the moment and will feed this example into the process."
What are the funniest or most ridiculous signs or stickers you've ever seen? Share examples in the comment box below or email pictures
- 'Feral' killer seagull 'munching' through Plumstead pigeon population
- UPDATE: Singing dogs come to Plumstead park this weekend
- High security as 'world's most poisonous garden' opens at the Horniman
- BEAKING NEWS: In a flap about Universal Credit? Head to Catford Nando's
- Jurassic Park - T-Rex dinosaur on a truck spotted in Greenwich