Corrective Services NSW has confirmed the possible exposure and is following the expert advice of NSW Health.

"All appropriate precautions are being taken as they continue to investigate," a Corrective Services NSW spokesperson said.

South Coast Correctional Centre has staff who travel from outside the Illawarra to work at the jail, although the spokesperson said "none come from Sydney at present".

As of August 17, no cases of COVID-19 have been contracted in prison by staff or inmate.

"The safety of all staff and inmates is our number one priority," the spokesperson said.

"And it will remain at the forefront of our decision-making processes while COVID-19 continues to pose a risk."

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Correctives says it is taking a wide range of precautions, including -

Continuing to follow the expert advice of NSW Health and work closely with the Justice Health and Forensic Mental Health Network (JH&FMHN) which provides healthcare in prisons.

A central COVID Command Post has been established to streamline and coordinate Correctives' efforts in response to COVID-19. The post operates seven days a week and includes representatives from all corrections branches as well as key areas such as Human Resources and IT, and the Public Service Association.

All staff are screened on entry to a prison or other CSNSW facility to identify those with symptoms of COVID-19, or who have visited any known hotspots or had contact with a confirmed COVID-19 case in the past 14 days.

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Staff and visitors are temperature-checked upon entry, and anyone with a temperature of 37.5 degrees or higher is not permitted into the facility," the spokesperson said.

"Staff are directed to follow health advice and get tested if they show possible symptoms of the virus, or if contract tracing confirms contact with a COVID-19 case.

"They must follow the relevant health advice applicable to their individual situation, including isolation and testing."

The screening and testing of fresh custody inmates is the responsibility of JH&FMHN.

On health advice, inmates are quarantined for a period of 14 days to help reduce the risk of the virus being introduced into facilities.

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"Inmates are not released into the main prison population until a negative result is received by JH&FMHNH, which is responsible for the provision of health services in correctional facilities" the spokesperson said.

"We work closely with JH&FMHN to monitor inmates at increased risk from infection including those with a history of respiratory illness.

"Any inmate who shows possible symptoms of the virus is isolated, provided with a surgical mask, and referred to JH&FMHN."

Prison transfers have been limited and include urgent medical escorts and transporting inmates from court cells to prisons.

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"We suspended all forms of external inmate leave except under special circumstances with the approval of the Commissioner, to reduce the risk of COVID-19 being introduced into the custodial environment," the spokesperson said.

"This includes inmates participating in work, education or training in the community, in addition to day and weekend leave.

"Personal protective equipment such as surgical masks and latex gloves as well as hand soap and hand sanitiser is available at our prisons and court cells.

"Masks are mandatory for all staff. Increased PPE requirements apply for staff in contact with fresh receptions and inmates in quarantine and isolation."

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There has also been increased cleaning at all our facilities, involving teams of dedicated staff and inmates, backed up by appropriate training.

With the support of Population Health, Correctives is training more staff to assist with initial information gathering for the purpose of contact tracing in facilities, the spokesperson said.

"This ensures impacted staff can be identified and assessed by Population Health quickly, and take all necessary precautions in line with Public Health Orders."