Some passengers have complained of being crammed into carriages with strangers refusing to wear masks on Welsh trains, despite Covid laws.
In Wales face masks remain a legal requirement on public transport, while in England they are only advised.
A number of passengers told BBC Wales people were ignoring calls to put on masks, leaving them feeling unsafe.
Transport for Wales (TfW) said it was urging travellers to wear masks on all services.
Since the start of the pandemic, 8,800 people have been barred from getting on a TfW train for not wearing a mask - with 2,047 people refused travel since the start of this year.
While most Covid restrictions were relaxed in Wales on 7 August, the wearing of face masks remains a legal requirement in most public places, including on buses and trains, unless you are exempt.
This is stricter than in England where face-mask laws ended on 19 July, with the UK government advising people to wear masks in crowded places.
cont
https://www.bbc.co.uk/news/uk-wales-58144669