Staff at an East Dunbartonshire secondary school are being balloted on strike action over "serious health and safety concerns".
A fire safety report published in November found there was a substantial risk to life from fire at Lenzie Academy and fire exits were not easily openable.
An indicative ballot saw 95% of EIS members vote in favour of industrial action, prompting the union to open a formal ballot until 30 January.
East Dunbartonshire Council said the fire report issues were being addressed in order of priority, with many already fixed, and the health and safety of staff and pupils was paramount.