HIQA has raised concerns about Letterkenny General Hospital and has identified a number of high risks.
It carried out an unannounced inspection on June 18 and discovered poor hygiene standards in various areas.
Inspectors found a anumber of areas of concern that warrented an immediate high-risk finding.
There was dust in many places, and some floors were not cleaned to an acceptable standard.
There were also brown stains in some toilets, red stains on some patient equipment, window leaks and flaky paint.
A follow up inspection found no significant improvement.
Meanwhile, a separate inspection at the Mater Hospital in Dublin found deficiencies in cleanliness and unsafe injection practices in the Intensive Care Unit.