Some 20% of personal protective equipment (PPE) that has arrived in the Republic from China does not reach the required standard for healthcare workers, the Irish health service chief said.
Paul Reid said just 10% of the total €200m order had arrived, and that suppliers have been told not to send any more of the kit that did not reach the standard.
Concerns were aired last week about some of the stock.
Speaking at the daily briefing in Dublin yesterday, Health Service Executive chief executive Mr Reid said 65% of the first batch was suitable for use.
A further 15% was "acceptable for healthcare worker use if the preferred product is not available".
This includes white overall gowns.
The remaining 20% of the order "does not meet the requirements for general healthcare use". "We will be using it for other specific purposes, perhaps in some of our isolation units and teams," he said.
"A specific issue here relates to some of the masks that don't meet our requirements for specific respiratory masks but they may be used for other purposes, and that represents about 20%.
"We have been in discussions with the supplier as we have identified this... we don't want any further delivery of this kit in the next orders."
He said samples with the revised specification were expected "at the back end of next week".