The Irish Nurses and Midwives Organisation says overcrowding in hospitals cannot be tolerated.
It comes as yesterday saw the worst levels of overcrowding since the beginning of the pandemic, with 395 patients being treated on trolleys.
Cork University Hospital was the worst affected, followed by Limerick and Galway.
INMO General Secretary Phil Ní Sheaghdha says more needs to be done to stop the problem continuing into the winter months.
"Overcrowding at any time is really, really bad.
"It's bad for patients, it's bad for staff, it's bad for longer term issues such as retention of staff, it causes a worsening of outcomes for patients, it's never good.
"But it is really bad during a pandemic, and going into the winter months where we traditionally have had excessive overcrowding we simply say it cannot be tolerated."
