A second hospital in Kerry is charging staff for boiling water.
Workers at Killarney Community Hospital have to pay for boiling water in the canteen, while staff at Kerry General Hospital have to pay 50 cent.
The Health Service Executive says the canteen is the only part of Kerry General where staff have to pay for water.
It says the charge was introduced because staff were bringing their own teabags into the canteen to avoid paying for tea.
SIPTU's Ted Kenny told Radio Kerry his union will be discussing the charge with the HSE.