The McGowan government is being accused of complacency as a second coronavirus infection control breach emerged at Royal Perth Hospital.
A fourth staff member at the hospital has gone into self-quarantine after they were seen removing their surgical mask prematurely while leaving the room of a COVID-positive patient.
"The breach (that) occurred yesterday afternoon was immediately detected and relevant processes enacted to ensure the safety of other staff, patients and the community," East Metropolitan Health Service chief executive Liz MacLeod said on Monday.
"In an abundance of caution, this staff member has been placed into self-quarantine and is being monitored daily for symptoms."
It comes just a day after a separate breach involving the same patient, the captain of the AquaGenie bulk iron ore carrier.
A service lift was not properly cordoned off after it was used to transport the man in his 60s from the RPH emergency department to the intensive care unit.
CCTV footage revealed three staff members who were not wearing personal protective equipment had unwittingly entered the lift within 15 minutes of the patient transport and prior to it being cleaned.
All three have gone into self-quarantine.
"Since March 2020, RPH has cared for more than 40 COVID-positive inpatients with no breaches," Ms MacLeod said.
"In light of the weekend incidents, a full review of our policies and procedures is being undertaken."
Two of the three were fully vaccinated against COVID-19, while the third had received their first dose, she said.
Liberal health spokeswoman Libby Mettam said the breach revealed "gaping holes" in the health department's protocols for managing infected patients.
"This seriously raises the question about what the McGowan government has been doing 12 months into a pandemic, where it can't effectively manage one patient," she said.
"The McGowan government has had more than a year to prepare and such basic measures and procedures should well and truly be in place."
Health Minister Roger Cook said the latest breach was still being investigated.
He revealed details of a plan to prevent people from working in hotel quarantine if they haven't been vaccinated against COVID-19.
About two thirds of hotel quarantine workers have been vaccinated, including about 30 per cent who have received their second jab.
Mr Cook said security guards had been the least compliant cohort.
A public health order is expected to be made on April 27 and will come into effect around May 10, with the government to use the interim period to consult with security companies and encourage individual workers to get vaccinated.
The AquaGenie vessel has departed Australian waters and set sail towards the Philippines after being docked off the coast of Karratha.
A legal direction had been issued blocking the ship from entering WA waters after a crew member returned a positive coronavirus test.
Both he and the ship's captain were removed from the ship and transported to Perth where they were placed in isolation in hospital.
Australian Associated Press