A nurse who took to Facebook to raise concerns about standards at his hospital has been cautioned by the nursing regulator.
Colin Stewart Toseland told friends on the social networking site that wards at Betsi Cadwaladr University Health Board's Ysbyty Glan Clwyd Hospital in north Wales were unsafe.
In postings made in 2010, he said the hospital had asbestos in it and that his bosses did not have enough money to pay the wages of nurses.
A Nursing and Midwifery Council panel ruled that the online complaints had impaired his fitness to practise.
However, panel chairwoman Teresa King said she viewed his errors at the lower end of the scale and imposed a 12-month caution rather than ordering a suspension or striking him off.
She said his mistakes were "deliberate, inappropriate and repeated" and "had the potential for public harm", although there was no evidence any actual harm took place.
Mr Toseland used Facebook in February 2010 to say wards were unsafe and there was asbestos in surgical theatres. The health board later carried out an asbestos removal programme.
He used the site to criticise his employers again six months later, and threatened to go public with allegations there was not enough money to pay nurses' wages.
At an earlier hearing the panel was told by case presenter Miranda Stotesbury that the NMC had clear guidance on whistleblowing, which she said had been "well-documented in the media".
"But there were plenty of mechanisms in place for the registrant to raise any concerns that he had," she said. "As a senior nurse he would have known this. He did not escalate his concerns through the proper and appropriate channels."