There has been a large drop in the number of people wearing face masks on public transport since COVID restrictions eased, Network Rail has said.
Some 20% of passengers are now wearing face coverings at train stations – down from a figure of 80% before restrictions were scrapped on 19 July, according to the train operator.
Current rules state that there is no legal requirement for commuters to wear a covering on public transport in England, but Transport for London (TfL) has kept the rule as a condition of carriage in the capital.
The government advice is that people are “expected and recommended” to wear masks if people come into contact with people they don’t know in enclosed and crowded spaces.
However it is up to transport operators to decide whether to implement their own policies, the government added.
Scotland, Wales and Northern Ireland have all kept face masks on public transport as law.
Mike Lynch, general secretary of the RMT union, told the BBC that his members had noticed more people ignoring the recommendations ever since the rules were changed in July.
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He said: "Even on London transport, where it is supposed to be a condition of carriage, just like paying a fare, the policy is coming apart at the seams and as more people see others failing to comply, the situation will escalate quickly over the autumn.”
Anyone failing to comply with the TfL condition of carriage may be refused travel, unless exempt.
However, just 221 passengers were stopped from using transport services and 53 people were told to get off in the seven weeks following the easing of restrictions, according to the Guardian.
Siwan Hayward, director of policing and compliance for TfL, said: "COVID is still with us and we all have a role to play in doing the right thing and keeping each other safe.”
He added that there was concern that people would no longer comply with the policy even if COVID cases escalate in the winter months.
A spokesperson for Unite, which represents bus drivers, said members were “being placed in danger” when boarding buses themselves to be taken to rendezvous points to collect buses.
They added: “Due to buses getting busier, they can't socially distance and feel their health is being placed at risk by non-mask-wearers.”
A spokesperson for the Rail Delivery Group said measures were in place to minimise the risk of COVID, including enhanced cleaning, and ventilation that refreshes the air in carriages every six to nine minutes.
They added that most people are "doing the right thing" and wearing face coverings, especially when carriages are busy.
London mayor Sadiq Khan has urged the government to bring back masks on public transport as a national requirement as he aired his concern that a “significant number” of Londoners were not wearing them.
He said: “This voluntary system, this condition of carriage isn’t working as effectively as before.”
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