More than 600 nurses, midwives, healthcare assistants, students and administration staff walked off the job at Waikato Hospital on Friday amid recruitment concerns.
The 90-minute stop-work meeting forced last minute cover of some services within the hospital while the New Zealand Nurses Organisation (NZNO) members walked to The Verandah at Hamilton Lake to discuss the situation.
Emergency Department nurse Tracy Chisholm said in her department alone they need 20 extra nurses and healthcare assistants.
Health New Zealand Te Whatu Ora had not followed an agreed safe staffing tool that determined the amount of nurses required, she said.
"We are short-staffed. We have identified what we need with a proven, validated tool and they are not providing the staff."
NZNO said Te Whatu Ora must immediately recruit and employ more staff to ensure safe levels throughout the tertiary hospital and the region.
NZNO Hauraki organiser Nigel Dawson said the union believed there were about 600 nursing vacancies across Waikato.
Oncology outpatient nurse Therese Van Kerkhoff said a hiring freeze was preventing the recruitment of much-needed extra staff.
Van Kerkhoff was an emergency department nurse but left and went to outpatients because she said the system was broken.
"I used to take up extra shifts. I no longer do that because it's too unsafe. I would actually spend all my time trying to follow up after my shift on getting stuff done for my patients.
"And my stress levels were too high. It was just like I see too many things that weren't done or couldn't be done with the lack of staffing."
Marchers held up signs and flags and cheered as passers-by beeped their support as they headed to the meeting.
The union wanted Te Whatu Ora to provide a healthy workplace by immediately beginning recruitment and employment of sufficient staff to ensure safe staffing levels and meet minimum ratios across all departments.
It said this was to provide high quality patient care, prevent burnout and fatigue among existing staff, and address workload pressures.
Members were also claiming backdated holiday pay from three years ago.
Health New Zealand group director of operations Michelle Sutherland said the organisation supported staff to attend stop work meetings and she was in regular contact with the NZNO.