impact of noise on childhood cognitive development

Poor classroom acoustics: The invisible reason Johnny can’t read.

Poor classroom acoustics create a negative learning environment for many students, especially those with hearing or learning difficulties. According to a report by David Lubman (“America’s Need for Standards and Guidelines to Ensure Satisfactory Classroom Acoustics”) “acoustical conditions in many classrooms are unsuitable for such tasks as learning to read, to listen or to understand unfamiliar material.” Poor classroom acoustics are frustrating for both students and teachers, as indicated in teacher surveys. According to the Acoustical Society of America, in many classrooms in the United States up to 25% of the information can be missed because of excessive noise and reverberation.

Studies have shown that poor classroom acoustics negatively affect learning. The sources of classroom noise can be interior noise (such as heating, ventilating and air conditioning – HVAC) and interior equipment such as the fans in overhead projectors and computers. Walls, ceilings, and floors not properly insulated can also contribute to noise. Noise sources can also come from exterior sources such as aircraft and highway traffic. Deficits in reading and language skills due to poor classroom acoustics are cumulative; therefore, the effects of poor classroom acoustics on the very young student can be devastating.

Poor classroom acoustics also impacts teachers (Bronzaft and McCarthy, 1975). According to David Lubman, “teachers are less likely to talk with students or will talk with them for shorter periods when noise levels are high.” When teachers have to raise their voices over background noise, their voices can become fatigued. Working in this environment on an ongoing basis can contribute to teacher frustration and even burnout.

In Dr. Lubman’s report, “America’s Need for Standards and Guidelines to Ensure Satisfactory Classroom Acoustics”, he indicates that the Swedish standard for an acoustically satisfactory classroom should not exceed 30 dBA when unoccupied and a dining room and gymnasium should not exceed 40 dBA. Many American classrooms have an unoccupied level of 50 dBA and gymnasiums can exceed 60 dBA. Noise levels can be measured with a sound level meter set to the A-weighting scale. Although many teachers may be aware that the noise is bothersome, they may not realize the impact the noisy classroom has on their own teaching and their student’s learning. According to the Federal Register, November 8, 1999, The Architectural and Transportation Barriers Compliance Board (the Access Board) will support the development of a standard on classroom acoustical design by the American National Standards Institute (ANSI) Committee on Noise (S-12), under the secretariat of the Acoustical Society of America (ASA).

It is critical that teachers, parents and administrators understand the impact that a noisy classroom has on student’s learning and work with noise control consultants and architects to create a quiet learning environment. There is no one way to quiet all rooms of a school. The school cafeteria, gymnasium and various classrooms each have different acoustical requirements. Even the teaching style (i.e., lecture, group discussion) has to be taken into account. The Acoustical Society of America recommends surveying classrooms and teachers to identify noisy environments. The use of acoustical tile ceilings, wall coverings, and bookshelves to absorb sound can help. An acoustical consultant can also be helpful to quiet the HVAC, control other noise sources and make recommendations to improve the overall listening and learning environment in the school.

Dr. Arline Bronzaft and Dr. Dennis McCarthy, in a landmark study in 1975, found that students’ reading scores were affected by noise. Dr. Bronzaft and Dr. McCarthy examined reading scores of children in a school where classes were located adjacent to elevated train tracks and compared them with reading scores of students on the quiet side of the school. The researchers found that by sixth grade, the students on the noisy side of school tested one year behind those on the quiet side of the school. In a follow-up study in 1981, noise abatement had been provided by the Transit Authority, and the Board of Education and Dr. Bronzaft found that reading scores between the two groups were now equal.

In a study by Gary Evans and Lorraine Maxwell at Cornell University (1997), it was found that children whose schools were affected by aircraft noise did not learn to read as well as those who were in quiet schools. The researchers compared children in a noisy school (in the flight path of a major international airport) with similar students in a quiet school and found that children in the noisy school had difficulty acquiring speech recognition skills, impacting on the ability to learn to read.

Researchers know what parents do—noise in the home brings chaos to our lives. Imagine a home at around 5 p.m. The television is on, perhaps the stereo is blaring upstairs. The phone rings, one child pulls at your leg, another screaming about a sibling knocking down a carefully designed block construction, all while you are trying to make dinner and help with the homework. Now, imagine the same home without the background noise. Turn off the television, turn down the volume on the stereo, and lower the voices. Theodore Wachs (1993) studied the level of “noise confusion” in the home and its impact on early childhood development. Wachs concluded that high levels of noise, crowding, and traffic patterns in the home were associated with lower caregiver attentiveness and responsibility. Noise, it seems, can affect the temperament and social interactions of children. Just like adults, children need quiet time at home, to create, learn, relax, and just “be.”

Where today’s market offers children a variety of noisy toys, loud and boisterous recreational activities and the message that “loud is cool,” parents must provide children with the opportunity for peace and quiet in their lives. Consider the words “peace and quiet.” In order to have peace, it is implied that we must have quiet. If we want children to live in a world of peace, we must first offer them a world with the opportunity for quiet.

Parents, teachers, and government officials must recognize noise as a serious hazard with deleterious effects to children’s learning. It is critical to provide children with quiet environments to read, study, learn, or just relax.

• Acoustical Society of America (ASA)
• The Access Board
• ASA's historical archive at Acoustics.org