Most of us have heard the saying if it’s too loud, you’re too old. That may be true in some circles, but in terms of health and well-being, too loud is more than a matter of preference. As acoustical consultants we normally concern ourselves with intelligibility, sound isolation, and room acoustics; however, it’s important to remember that sound can have other effects on us. It’s common knowledge that high sound levels can damage your hearing, but sound can negatively impact us in other ways. Read on to learn more about the physiological and performance effects high sound levels can create.
For hearing damage to occur in most people, an environment must be sufficiently loud for a sufficiently long time. One of the most common guidelines in this regard is set by the Occupational Safety and Health Agency (OSHA). For work environments exceeding 85 dBA, an employer must administer a hearing conservation program. At 90 dBA, OSHA defines a permissible exposure limit of 8 hours. For every increase of 5 dB, the length of allowable exposure is cut in half. Therefore, a worker may only spend an hour in an environment with an average sound level of 105 dBA, and only 30 minutes in a 110 dBA environment. That’s as loud as some rock concerts, so check your watch the next time you’re tempted to call for an encore.
Few of us would debate that loud sounds during sleep can wake up all but the deepest sleepers, but the effects of high sound levels before we sleep can also be detrimental. Eight hours of exposure to sound levels of 75 dBA or more can reduce the length of time a person spends in deep sleep states when compared to someone who spends eight hours before sleep in a quieter environment. Furthermore, those exposed to loud sounds are shown to have higher cortisol levels, a hormone responsible for the symptoms of stress including irritability, anxiety, and fatigue. Other effects may include elevated blood pressure and heart rate, which can have long-term health repercussions.
An influential study was conducted in the 1970s on school children near an elevated train track in an urban environment by Arline Bronzaft. One group of children was in classrooms adjacent to the tracks while another group was on the other side of the school. It was found that students on the quiet side performed better on reading tests, and eventually surpassed their peers in the louder classrooms by a full grade level. A contributing factor in this case may have been that the children in the louder rooms simply had difficulty hearing the teacher; however, other research has shown that noise exposure can affect concentration, memory, and cognitive performance.
Struggling to hold a conversation in a loud restaurant or being distracted by a blaring car radio may only seem to be annoyances, but the cumulative effect of high sound levels can be much more insidious. While the world may not seem to be quieting down, awareness and consideration can go a long way in leading a peaceful and happy existence for you and your neighbors. If it’s too loud, turn it down!