Hospitals across the country saw the second-highest levels of overcrowding on record for the month of June.
Figures from the Irish Nurses' and Midwives' Organisation show 8 thousand 312 patients, including 164 children, were left waiting on beds last month.
That's a 17 per cent decrease compared to this time last year.
Sinn Féin's health spokesperson, David Cullinane, says a lack of staff and beds is contributing to the problem:
He said: "I've been saying to the Minister for Health for some time that the capacity issues in hospitals of not having enough staff or beds are leading to the average wait time is now over hours 12 hours for admission to a bed from an emergency department.
"But we know in some hospitals its over 24 hours and in some cases people are waiting days on end."
