It had not been in a position to respond directly to the union.
DHB chief nurse and midwifery officer Chris McKenna said she was very disappointed NZNO hadn't first discussed this with her and given her an opportunity to respond.
"We have worked very hard in conjunction with NZNO on the Care Capacity and Demand Management programme, (CCDM) which is a nationally agreed programme to match nursing capacity to patient demand," the officer said.
"Hawke's Bay was one of the first DHBs in the country to implement this, and more than $2.5 million has been spent recruiting new nursing staff in the past two years, and more investment is planned. NZNO publically congratulated us on our work with this programme as recently as 10 November, 2018."
McKenna said Hawke's Bay Hospital was a "very busy hospital", both in terms of patient demand and as a training hospital.
"However, both management and the Board are actively working to address areas of concern so the growing demand on services does not impact on patient safety.
"This is the focus of all our current planning and we are working constructively with senior clinicians to achieve this.
"Hawkes Bay DHB has implemented a people plan to support its staff through many wellbeing initiatives and nursing staff have played an active role in developing this plan," McKenna said.
Brinkman said that what the union and professional association was hearing from Hawke's Bay members was "alarming," but no response had been received from management to the concerns.
"Nursing staff have been expressing and documenting their health and safety concerns with management repeatedly and at every shift because they pose a significant danger to both patients and staff," she said.
"Despite this, no response has been received from management and nothing has happened to mitigate these systemic weaknesses."
There had been "increasing disquiet" about risks arising from high bed occupancy, inadequate staff numbers and skills mix and increasing incidents of violence and aggression by patients, she said.
"Staff are fearful and say their ability to care for patients has been seriously diminished," Brinkman said.
"Managers at HBDHB must recognise their responsibility to staff under the Health and Safety at Work Act and promptly produce an action plan to resolve these concerns."
She said nurses are "leaving their shifts in tears and many are actively seeking alternative employment".
"This is a really serious concern as recruiting to nursing vacancies and retention of nursing staff has already been identified as an ongoing problem at the DHB," she said.
She also said the impact of the resident doctors' strikes had been significantly underestimated and that the strikes could not have gone ahead without the tangible support of nurses at an already difficult time.
She said the NZNO has asked the DHB to account for how it will address the health and safety concerns raised by nurses in the short- and medium-term, and has requested a response within one week.