Voice is a basic tool for teachers. Chronic voice disorders, very common among teaching staff, cause long term sick leaves or leaving the job for good (for other profession or for disability pension). In Poland, chronic voice disorders as a group of diseases are formally recognized as occupational disease. In 2007, officially confirmed voice disorders cases were the biggest group (24,4%) of all occupational diseases in Poland
According to Nofer Institute of Occupational Medicine in Łódź, 70% of teachers suffer during their career different forms of temporary or permanent voice problems (hoarseness, painful speech difficulties, or even aphonia). For teachers, voice disorder risk is five times bigger than for other “voice-working”professionals like lawyers, priests or singers.
Phoniatrists point out the main risk factors:
– noise and low speech intelligibility in most classrooms force teachers to speak too loud
– too dry and dusty air in the classroom
– air currents
– lack of voice emission training
Since 80’, chronic voice disorders are on the Polish, official occupational diseases list. The formal name of this illness is “chronic voice disorders due to excessive vocal effort lasting at least 15 years”. This general term contains three different diseases: hard vocal nodule, secondary hypertrophic changes of vocal folds, paresis of adductor and tensor vocal fold muscles with glottis insufficiency and persistent hoarseness. In last few years there is stable number of new, formally confirmed cases: about 800 per year. During 20 years, between 1988 and 2007 there were 40.000 cases – when average number of active teachers in Poland was 550 thousands. The teacher with formally confirmed voice disorder has a right for fully paid sick leave (maximum three sick leaves, a year long each) or for disability pension. In 2000 polish Ministry of Education estimated occupational diseases in education (which are in 98% voice disorders) cost for 25 milions €.
Teachers generally work in rooms (classrooms, lecture theatres, sport halls etc). These rooms should be designed, built and furnished in the way to provide the best possible environment for teacher’s vocal effort. The room acoustic comfort is the key factor.