Do Teachers talk too much? Some pupils may well think so, but for most in the profession the ability to maintain a strong vocal delivery for hours on end is essential in getting across information and keeping order.
"Teachers depend on their voices as one of their professional tools," says Roz Comins, co-ordinator of the Voice Care Network UK, a charity. "But unlike actors and other professions, they are not trained to use them effectively - and this can lead to problems."
In extreme cases, voice disorders have forced teachers to cut short their careers; fortunately, this is rare. What is more likely is that a teacher will suffer a series of seemingly minor sore throats and periods of voice fatigue, which culminate in complete voice loss and recurring pain. At this point, a hospital voice clinic and a prolonged programme with a speech and language therapist may be the best chance of recovery.
According to VCN, teaching staff are particularly vulnerable to long-term problems. "Teachers have to talk and hold their students' attention for long periods, week in week out," says Ms Comins.
"They may also be fighting the acoustics of the gym or swimming pool, poor classroom design, a noisy group activity, or an enthusiastic music lesson in the room next door. All these can force them to strain constantly to keep the volume up."
Dry, dusty school buildings only add to the problem, while other factors include stress and staff shortages. "Teachers often work through colds, throat infections and even laryngitis when they should be resting their voices," Ms Comins adds.
The Voice Care Network believes that most teachers' vocal problems are preventable. "Understanding how the voice works, and learning simple techniques to control it and produce it effectively, can make a huge difference. Concentrating on your breathing and posture, easing out muscle tension, and drinking water regularly will bring great dividends to professional voice-users," Ms Comins says.
During the 1980s, speech therapists realised they were treating significantly more teachers in their clinics than any other profession, so they began to investigate. From this work, the Voice Care Network was created in 1993, with its mission to show teachers how to keep their voices healthy and to communicate effectively. The network now has upwards of 100 voice tutors running practical workshops across the UK.
Today, teachers are still statistically more likely to be patients in voice clinics than any other group of workers. As a specialist speech and language therapist at Belfast City Hospital, and a member of the VCN, Valerie Morton has treated many teachers.
She says: "Their problems range from a constant dry throat, discomfort, soreness, a scratchy sensation, hoarseness, vocal tiredness and the need for great effort to produce an audible sound, right through to losing the voice completely and severe pain."
Such was the fate of one young teacher who, after three years of working, began to lose her voice on a regular basis. In some pain, she visited her GP, who referred her to a voice clinic. After 11 months of speech therapy she is now able to manage and prevent her "poor voice days".
She has also regained her confidence in front of pupils, something which had been dented because she was unable to rely on having enough vocal power to run a teaching session. Looking back, she makes a telling observation:
"I was sad, however, to realise that the vocal problems I encountered could have been prevented had I received voice training as a student teacher."
Part of the VCN's work includes presenting workshops to trainee teachers at universities around the country, highlighting the importance of such voice care early in teachers' careers.
Ms Comins says: "Teachers usually have no experience of using their voices professionally, and the toll it takes comes as a shock during their first year. Many complain of constant sore throats and strained voices."
When such symptoms recur frequently, they can be a warning signal of other long-term problems ahead.
"Unfortunately, teachers cope too well, believing that a weekend's rest will be enough," she adds.
"But ongoing voice and throat problems are not an occupational hazard, and practising simple techniques can free teachers from regular discomfort and pain."
VITAL VOICE ADVICE
* Warm up your voice before you start, by humming or doing vocal exercises
* Relax shoulders, neck and throat
* Stand up straight and breathe deeply from the diaphragm
* Ventilate the room
* Tackle dry atmospheres with bowls of water on radiators, etc
* Drink frequent sips of water
* Don't clear your throat - swallow instead
* Reduce background noise as far as possible
* Avoid shouting or whispering, as both are damaging
* Allow time to rest your voice.