A stunned van driver was slapped with a hefty £200 fine – for not displaying a No Smoking sticker in his vehicle.

Trevor Emery was fined four times more than if he had actually been caught puffing at the wheel when he was booked by a city council warden in Watling Street, Canterbury.

The washing machine repairer, who does not smoke, was left bewildered by the little known law, which makes it compulsory to display a No Smoking sticker in a work van.

Trevor, who lives in Whitstable, and works with his son, Lee, said: “We were completely oblivious to the law.

"I’m sure that if you walk the streets of Canterbury looking in the windows of work vans you won’t see many of the stickers.

“Apparently it came into force in 2006 but we had not been made aware of it.

“Of course, if we had known then the sticker would have been in the van straight away.”

Trevor and Lee, who run their own domestic appliance business, Wash Freeze, were delivering to a job when hit with the fine.

“If we were actually caught smoking in the van, the fine would be just £50 – that is just ridiculous,” Trevor said.

“Surely the best thing to do was to give us a fair warning and tell us to get a sticker – but that didn’t happen.

“We were parked on double yellow lines, which we are allowed to do for unloading, so I thought the officer would bring us up on that. But then he said about this weird law.

"I was expecting a £30 fine or something like that, but a larger one seemed ominous when I asked the officer and he was reluctant to say – the figure he said was just ridiculous.”

The law states that businesses must display No Smoking signs in all workplaces and vehicles.

Fines can reach in excess of £1,000.

The business owner added: “As I paid the fine within two weeks, it was reduced to £150, but that is still unfair.

“I appealed but we were unsuccessful, so we have now warned others about this law.

“Hopefully others won’t be caught out – and we definitely won’t as a No Smoking sticker was put in the van straight away.”

Head of safer neighbourhoods Doug Rattray said: “It is an offence to not display a No Smoking sign in a vehicle that is used for commercial purposes.

“This is the case regardless of whether someone is self-employed, the only person to use the vehicle or if nobody smokes in it.

“We enforce this but the level of fine is set nationally in law.

“Mr Emery received a fine, which he paid, for this offence. He was advised on the legislation and given the correct sign.”

Council spokesman Rob Davies confirmed that around 50 fines have been issued since the law came into force.