Patients too will be supplied with masks which they are required to wear, where possible, under the rule which applies to all public hospitals and community health settings across the state.

Visitors should wear their own mask, according to the Illawarra Shoalhaven Local Health District (ISLHD), as stocks need to be prioritised for staff and patients.

Read more: Two men diagnosed with COVID-19 in the Illawarra

Dr Bruce Ashford, a surgeon and co-ordinator of the Wollongong Hospital COVID-19 Task Group, welcomed the move which came into effect on Friday.

"There is an increase in community transmission in some parts of the state at the moment, and this is one of the ways we can protect our hospitals and the people within them," he said.

"Having staff, patients and visitors wear masks adds another physical barrier from infection from asymptomatic people - people who don't know that they're ill, that they're harbouring the virus and could inadvertently spread the infection."

Most staff would be required to wear masks, with the exception of those who did not come into contact with patients such as administrative staff. Only some patients would be exempt.

"There are some patients who would not be able to be compliant with the directive - such as those who are cognitively impaired in some way," Dr Ashford said.

"It's difficult also to have children wearing masks so they are not required for paediatric patients, or for patients with certain conditions including respiratory or cardiac disease."

Dr Ashford said it was important people understood that masks should be used in addition to - but not in place of - other precautions such as hand hygiene and physical distancing.

"We want to stop the spread of COVID in the community - and importantly hospitals," he said.

"So people should stay away from the hospital if they can - and not stay longer than they need to; and they should continue with other measures such as hand-washing and social distancing.

"Mask-wearing is just part of an overall strategy to protect the inside of the hospital from asymptomatic carriage of COVID."

Dr Ashford said while there had been shortages of personal protective equipment (PPE) including masks at the start of the pandemic, stocks were now adequate.

"PPE is the currency of the pandemic and we're very mindful of that," he said.

ISLHD chief executive Margot Mains said the district would continue to respond quickly to help keep patients and staff as safe as possible as the COVID-19 situation evolved.

"While there is currently no evidence of community transmission in the Illawarra Shoalhaven and our case numbers remain low, this additional precautionary measure is being taken to ensure our strong position is maintained and the risk of potential spread is reduced,'' Ms Mains said.

"From (Friday) all healthcare staff, patients (where possible) and visitors will be required to wear a mask when in a health facility (children 12 years and under are not required to wear a mask).

"The district thanks staff and the community for their ongoing support in these challenging times."

NSW Nurses and Midwives Association general secretary, Brett Holmes, said the NSW Health directive highlighted the workplace risks for nurses.

"While we welcome the decision to move to an amber alert, this clearly demonstrates our members have been working in much higher risk environments than the health service has been prepared to admit," he said.

"Since the beginning of the pandemic, nurses and midwives have endured ongoing issues with access to adequate personal protective equipment (PPE) and, at times, conflicting infection prevention advice."

Mr Holmes said the union would continue to pursue NSW Health over the issue of 'fit testing' and 'fit checking' for P2/N95 masks where required.

The new requirement to wear masks doesn't apply to private hospitals, GP clinics or aged care facilities - though non-public healthcare settings can opt to put the measure in place. The Mercury understands Wollongong Private Hospital is introducing the measure, to maintain a consistent approach with NSW Health requirements.

Meantime Ms Mains said hospital visiting hours had also changed within the district, with visiting only available from 11am to 1pm and 5pm to 7pm.

Only one visitor is allowed in each visiting session for each patient, and she said it was recommended that the same person does not visit in both sessions in one day.

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