The Waitemata District Health Board says if management is still telling staff to remove masks "it's a real problem" and "it should not be happening".
The DHB's Chief Medical Officer has also told Newshub there are "no" issues with bullying, despite nurses telling Newshub such a claim is laughable.
DHB bosses spoke to Newshub today, where they defended their handling of staff rostering at Waitakere Hospital and say if staff are still being asked to remove masks by managers at North Shore Hospital, it's inappropriate.
It comes after another nurse at Waitakere Hospital has tested positive for COVID-19, bringing the total number or nurses confirmed to have the virus to four.
In total, 42 staff are now off work at Waitakere Hospital.
"It's very distressing to us to see one of our colleagues get unwell and our thoughts really go out to that nurse," said Waitemata DHB chief medical officer Dr Johnathan Christiansen.
Nurses told Newshub they'd specifically requested for this to not happen. A week on from that, the clinical lead on COVID-19 says he's yet to speak to management about those concerns.
"I'm not aware of any concerns raised to managers at the hospital," Waitemata DHB clinical lead in the COVID response Dr Willem Landman told Newshub.
The chief medical officer says communication is improving - thanks to Newshub.
"It's been really helpful to have a channel of communication opened up through you because some staff have been more prepared to talk to you," Dr Christiansen said.
The DHB says expert advice was that hand washing, distancing and PPE use were the most important safety measures. However, it's now dropped the policy of mixing wards on the roster
On Thursday, two North Shore nurses said they'd been told to remove masks by management as "it may scare the patients". A third nurse was nervous about asking for a mask fearing she could be bullied.
On Friday, Dr Landman told Newshub staff being told to take masks off is inappropriate.
"If it is happening, still, right now, then that's a real problem," he said.
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And on the subject of bullying, Dr Landman said, "We've got an organisation that's large enough that I would expect somewhere within the organisation, there may be bullying."
But the chief medical officer is clear bullying is not an issue.
"It's not part of our culture, it's never been part of our culture," Dr Christiansen said.
The DHB denying that bullying is an issue has been described to Newshub as "laughable". One nurse said she "could go on for hours about examples of bullying".
She said claims by the DHB that PPE is readily accessible are "not true", saying, "We only have a certain amount for use, and the rest is locked away".
Asked by Newshub why the PPE was locked up, Dr Christiansen said, "The PPE is available for the appropriate use".
He said N95 masks may well be locked up but surgical masks are freely available, and if they aren't, staff need to contact them.
Watch Michael Morrah's full interview with Waitemata DHB chief medical officer Dr Johnathan Christiansen and Waitemata DHB clinical lead in the COVID response Dr Willem Landman below.