Ronnie Smith, general secretary of the Educational Institute of Scotland, said more and more cases were being reported to the union. A recent TUC report, Work Hoarse, showed that teachers and call centre staff were the two groups of workers most likely to suffer from voice loss.

Voice strain could develop into a serious occupational health condition which could hinder the way people did their jobs and cause difficulties for schools, colleges and universities due to the loss of experienced staff, Mr Smith said.

“The lesson for educational employers is that you must take the issue of voice strain seriously and listen to teachers or lecturers when they report their concerns,” he commented. “There should also be the opportunity for adequate breaks and welfare facilities and easy access to fresh, clean drinking water for teaching staff.

Mr Smith also called for teacher education institutions to train students in speaking techniques. “In many public service jobs such as teaching and lecturing, talking is an essential component. However, we need to drive home the message that, while talking is clearly not avoidable in these professions, voice loss is.”