The General Secretary of the INMO, Liam Doran, has said he expects nurses and midwives to vote in favour of industrial action.
The union is calling for pay restoration, as well as recruitment and retention initiatives.
It says members have to deal with chronic, persistent overcrowding with insufficient numbers of staff.
Liam Doran said: "Genuinely, based upon the anger that we got in the 12 regional meetings, the total frustration, the lack of respect that's being shown to nurses on the frontline and midwives over the last number of years, I think we'll get a strong mandate.
"But democracy has to do its thing."