One in three ambulances operated by Dublin Fire Brigade was out of action last night because of mechanical faults, according to figures released by the Irish Fire and Emergency Services Association.
It also says several ambulances in the 17-strong fleet are unsafe because they are "beginning to fall apart" while the vast majority have more than 300,000kms on the clock.
Chairman John Kidd is calling for action and warning that the dangers to both crews and patients are obvious.
"Unfortunately there will have to be a major disaster in the greater Dublin area, or in Ireland in general, before the concerns of the ambulance service nationally are dealt with," he said.