The study, conducted in
Researchers found that Grade 1 pupils, on average, miss one in every six words spoken by teachers.
"More than 90 per cent of Grade 1 classrooms had inadequate listening conditions," said Linda Rammage, spokeswoman for the Canadian Association of Speech-Language Pathologists and Audiologists.
Some of the noise comes from the typical physical environment of a school, Dr. Rammage said.
"Desk and chairs scraping on the floors as students move around, equipment, computers, projectors, fish tanks, ventilation and cooling systems, lighting systems," she said. "Often, rooms are very poorly designed and have too many hard surfaces."
Many teachers also strain their voices to be heard above classroom background noise, Dr. Rammage added.
But the problems, particularly with noise coming from high-tech equipment that has permeated classrooms in recent years, can be reduced by some simple remedies, including improved acoustics, one audiologist said.
"We are creating classrooms that are very technologically advanced in a
lot of ways [but] we're creating a problem," said Andre Lafargue at River Valley Heath in
"If we can find ways to maybe hide the computer. Even a simple panel ... would absorb some of that sound and it would not just escape into the soundscape environment of the classroom."
Speech-language pathologists say teachers working in poor acoustic conditions often speak louder, straining their voices.
Studies have shown that a disproportionate number of teachers compared with other professions end up in voice clinics, making up about a quarter of the clinic caseloads, the association says.
When teachers strain to get through to their students, their voices become hoarse, making hearing them over background noise even more difficult.
The noise problem is often compounded by the reverberation of sound within a classroom as it bounces off uncarpeted floors and flat, hard walls.
As well, noise comes from neighbouring classrooms, hallways, gyms, music rooms and traffic outside schools.
The association offers tips for reducing noise levels, including putting something soft on the bottom of chair legs or installing carpeting in classrooms.
One inexpensive way to reduce the scraping noise of chairs and tables on classroom floors is to cut an X-slit in tennis balls and place them under the legs of the chairs and tables.
Other, more expensive options include installing hypoallergenic carpeting and curtains in classrooms, installing amplification systems or suspending acoustic ceiling tiles and sound-absorbent panels from upper walls.