After six months of turning up the heat on the Government, secondary teachers are now planning to test the temperature in their classrooms.
Members of the 11,000-strong Teachers' Union of Ireland (TUI) have been directed to monitor the temperature in their classrooms and leave if they are too hot or too cold.
Teachers are notified of the directive in the latest edition of TUI News, the union's newsletter.
With admirable attention to detail, the directive says the temperature should not drop below 17.2 degrees.
If it does, the teacher should raise the issue with their union and ask the principal to "remedy any defects in the heating system". Failing that teachers are instructed to leave the classroom.
The teachers' aversion to chilly classrooms does not mean they want to bask in the heat either. The directive says if the classroom temperature exceeds 26 degrees, similar action should be taken.
Allowance is made for "solar gain and humidity" but once the "shade temperature" exceeds this level, action should be taken, says the directive.
The wider implications of global warming on classroom temperature is not mentioned in the directive.
Commenting last night on the directive, one senior TUI official said that while freezing or sweltering classrooms were a genuine problem, other steps might be taken before teachers had to leave rooms, such as opening windows.
The directive was intended to bring schools into line with the Office Premises Act.
There is no reason why schoolchildren and teachers should be asked to bear temperatures - either hot or cold - which are not acceptable in an office environment, said one TUI source.
The directive is one of five issued to members. The others cover substitution, class sizes, travelling between schools and the length of the school year. The last one directs members not to return to work prior to September 1st even if the school imposes an earlier date.
The TUI, unlike the ASTI, is participating in the Government's benchmarking pay review body. It hopes to gain a significant increase from this process.