Video report by ITV News Meridian's Malcolm Shaw
British Transport Police is stepping up patrols on trains across the South East to ensure all passengers who can wear face coverings do so.
Since wearing a face covering became law in stations and on trains, the vast majority of passengers have done so with only a minority resisting the rules.
Those who refuse to wear a face covering risk being ejected from the train or station, or even fined up to £6,400.
passengers fail to wear a face covering on trains and at railway stations
To combat the problem, a pilot project is underway between British Transport Police and rail enforcement officers.
The patrols have proved a great success, boosting compliance from around 90% to almost 99%.
Across England, around 4,500 people have been asked to leave the railway for not wearing a mask with 140 people being fined.