Cathy Marshall says there is a one-way route from the hospital entrance off Howick Street to the exit on to Mitre Street due to the construction of the new MRI.

"Pedestrian access to the hospital's main and emergency department entrances remains the same," Ms Marshall said.

"We urge patients, carers and visitors to please follow the signage, directing the traffic.

"These changes are in place to ensure the safety of our patients, visitors, staff and construction workers."

Ms Marshall said she would also like to remind the community that the drop-off area at the hospital is only for drop off and not for parking.

"We appreciate everyone's co-operation and understanding during this time," she said.

Work started on the $4.92 million MRI machine in May and construction is on track to be completed in November.

The hospital will also be getting a $200 million redevelopment in the coming years after a budget announcement made earlier this year.