The INMO are warning that this winter could see the worst hospital overcrowding ever recorded.
It comes as the union say the number of people waiting on trolleys at Cork University Hospital is fast approaching levels last seen before the pandemic.
738 people spent time without a bed at the hospital's emergency department in August, with the INMO now repeating their call for more staff and additional beds.
The union say front line staff are also suffering from burn out and exhaustion due to the pandemic...
Speaking to RedFM News, Liam Conway from the INMO says immediate action is needed.
"We are predicting that the overcrowding is going to be one of the worst ever recorded.
"You throw Covid-19 into the mix in terms of that as well, that poses a serious hazard in terms of people who already have underlying conditions in our community, and who are not able to get access to the relevant services as well.
"Then you have understaffing and vacancies across Cork hospitals and maternity services, and you compound that with Covid-19 within the workplace.
"That poses a serious threat to both patient safety and our members' safety."
Meanwhile Cork University Hospital has advised patients to consider all options before presenting at the hospital's ED if their needs are not urgent as it is extremely busy at the moment
The hospital is asking the public to contact their GP in the first instance
They are also reminding people that they can avail of treatment for issues like cuts, sprains, minor burns and fractures at St Mary's Health Campus in Gurranabraher and local injuries units at Bantry and Mallow General Hospitals.