A new national policy is to come into force, which says face masks are to be worn in all settings for any healthcare workers providing care within two metres of a patient.
The Irish Nurses & Midwives Organisation (INMO) says it welcomes the change, which also applies to workers who come within two metres of each other for more than 15 minutes.
In practice, the INMO says this will mean nearly all frontline healthcare workers will wear face masks.
It says until now, many parts of the health service did not require or permit staff in all areas to wear this form of personal protective equipment (PPE).
The new official guidance states: "Surgical masks should be worn by healthcare workers when providing care to patients within 2m of a patient, regardless of the COVID-19 status of the patient.
"Surgical masks should be worn by all healthcare workers for all encounters, of 15 minutes or more, with other healthcare workers in the workplace where a distance of 2m cannot be maintained."
The INMO says it wrote to the HSE's Chief Clinical Officer Dr Colm Henry on April 3rd, calling for this new measure to be rolled out
While several hospitals - including the largest St James’ Hospital - have already got such a policy in place.
INMO General-Secretary Phil Ní Sheaghdha, said: "This is welcome news to frontline staff and patients, which should ease some anxiety and reduce transmission of the virus.
"This should have been rolled out weeks ago, but we are glad to have finally secured this measure.
"It will not only benefit frontline healthcare workers, but will reduce the risk of transmission to patients.
"The next step must be ensuring sufficient supplies are available for all health workers, and continuous PPE training where needed."