Recruitment problems in the sector, where vacancy rates constantly average more than 5%, are already so severe that it is not uncommon for care homes and homecare agencies to display “Hiring now” banners. Anecdotally, UK citizens are seen as reluctant to apply for roles typically paying little more than the £7.20 minimum hourly wage at age 25 or over.

An estimated 6% of jobs in the sector are filled by EU migrants. That may not sound much, but the vast size of the social care workforce means that this figure equates to 80,000 people in England alone. Free movement of labour across the EU is “very helpful” to social care employers, says Martin Green, chief executive of Care England, which represents leading care providers.

Figures from the National Minimum Dataset for Social Care, compiled by sector skills agency Skills for Care, suggest there are more than 1.3 million social care jobs in England, excluding personal assistants employed direct by people with care needs, of which 82% are filled by UK nationals and a further 12% by non-EU citizens.The loss of non-British EU workers would be felt far more in some regions than in others: their proportion of the social care workforce doubles from the average 6% to 12% (20,000 jobs) in London and rises to 10% (21,000) in the rest of the south-east, but is as low as 1% (1,000) in the north-east.

Could they be replaced by workers from the rest of the world? Green says: “Given that one of the planks of the Brexit campaign is to reduce immigration, I think it highly unlikely that they would relax controls on people entering the country to be part of the care workforce.”

Introduction this year of the £7.20 “national living wage”, a 50p increase on the previous floor, has put strain on many care employers who say they cannot pay above the minimum because of below-cost fees paid for state-funded care by local councils. But the move was ordered by the UK government and had nothing to do with the EU.The European working time directive limits working hours to an average 48 a week and guarantees rest breaks and leave. These have proved important backstops in a sector where exploitation of staff has not been unknown.

The European convention on human rights, given statutory force in the Human Rights Act (HRA), has played an increasingly important part in social care. Last year, a care home in Hartlepool, Admiral Court, was shut down after inspectors found it was breaching residents’ rights to liberty and non-discrimination.

The inspectorate, the Care Quality Commission, has explicitly adopted a “human rights approach” to its work because, it says, “respecting diversity, promoting equality and and ensuring human rights” should be part of its core purpose.While adherence to the convention is distinct from EU membership, – and the government separately plans to replace the HRA with a British bill of rights – Brexit could mean that any future equality and human rights protections agreed by the EU would not be binding on the UK.