The nurses, all members of the Irish Nurses' Organisation, are protesting against what they describe as "unacceptable conditions" for staff and patients caused by a lack of ward space in the hospital. They are refusing to put up additional beds on any wards.
The acute hospital has an empty wing. Even though funding was recently allocated towards fitting it out, no work is expected on the site for at least two years.
The Midland Health Board and the INO are both due at conciliation talks in the Labour Relations Commission on Thursday.
