Physiological and psychological stress reactions in relation to classroom noise.

OBJECTIVES: This study tested the hypothesis that classroom noise is related to stress reactions among primary school children. Stress was monitored via symptoms of fatigue and headache, systolic blood pressure, reduced diurnal cortisol variation, and indicators of emotional distress. METHODS: In three classrooms of pupils in the fourth grade (10 years of age), daily measurements of equivalent sound levels (Leq) were made during 4 weeks, evenly distributed from September to December. One day each week of the study, the pupils answered a questionnaire about disturbance and symptoms, and blood pressure and salivary cortisol were measured. In the first and fourth week, the children also performed a standardized drawing test concerning emotional indicators. RESULTS: Daily measurements of equivalent sound levels in the classes (Leq during schoolday) ranged from 59 to 87 dB(A). Equivalent sound-levels were significantly related to an increased prevalence of symptoms of fatigue and headache and a reduced diurnal cortisol variability. Blood pressure and emotional indicators were not significantly related to sound levels. CONCLUSIONS: Current sound levels in Swedish classrooms may have a negative health impact, being directly or indirectly related to stress reactions among children. This finding indicates that noise should be focused on as a risk factor in the school environment.