The PSC has become the latest body to pile pressure on the home secretary.
The largest union in the UK Border Agency has written to Theresa May to highlight concerns over borders, on the day that Olympic athletes start to arrive at Heathrow.
The home secretary will face MPs over the Olympic security fiasco this afternoon, after Speaker Bercow approved an urgent question on the matter.
In a letter released today, the PCS's national officer for the Home Office Paul O'Connor said there was anecdotal evidence that staff were being told they couldn't go to the toilet, as desks have to be manned at all times.
He writes of other anecdotal evidence:
- Staff at Terminal 1 took a call from the enforcement team about a Brazilian national who claimed to have arrived a few days ago, but their passport stated they arrived over a year ago. It transpires that a contingency member of staff stamped the passport with the wrong year and the lack of Chief Immigration Officers meant that the stamp was not checked before processing began
- Police contingency staff informing experienced immigration officers that they had made a mistake in allowing a Turkish national entry without having indefinite leave to remain, when in fact there was an indefinite leave to remain stamp on the documentation
- Inadequate provision of UV lamps on desks to check documentation
- Relief staff being advised that they should not question visa nationals
- Staff being told that they cannot take any breaks, including drink and toilet breaks, as desks have to be 100% staffed. Scope for staff picking up cases has not been factored in.
All eyes will be on May's response to the G4S saga, with accusations that the Home Office knew of the problem 10 months ago.
But the department is also juggling concerns over border staff - as I wrote about here.
And the move comes on the same day that Telegraph readers voted May the cabinet minister most want to see sacked.
It doesn't look good, but it rarely does for a home secretary.