The INMO has said the emergency department at University Hospital Limerick is totally unsafe, with nurses in despair.
Waiting times of up to 18 hours were reported yesterday and there are fears of a repeat today.
The organisation representing nurses and midwives has said it is essential that all doctors and available personnel are brought in to help alleviate the pressure.
Mary Fogarty, Mid West Industrial Relations Officer of the INMO has said it has been “chaotic” over the whole Christmas period.
“It was absolutely out of control,” said Fogarty.
“It’s the same this morning, it was the same all day yesterday and it has been like this since prior to Christmas. During the Christmas period it has been absolutely chaotic.
“Yesterday there were in fact up to 18 hour delays for patients to see an emergency department doctor, that reduced down to five hours yesterday evening. But again this morning there are 15 hour delays for patients to see an emergency department doctor.”