Outrageous Sound And Human Health (II)

Cont’d from last Wednesday.

Child physical development

According to Lester W. Sontag of The Fels Research Institute (as presented in the same EPA study): “There is ample evidence that the environment has a role in shaping the physique, behavior, and function of animals, including man, from conception and not merely from birth. The fetus is capable of perceiving sounds and responding to them by motor activity and cardiac rate change.” The effects of noise exposure are highest when it occurs between 15 and 60 days after conception, a period in which major internal organs and the central nervous system are formed.
Later developmental effects occur as vasoconstriction in the mother reduces blood flow and therefore oxygen and nutrition to the fetus. Low birth weights and noise were also associated with lower levels of certain hormones in the mother. These hormones are thought to affect fetal growth and to be good indicators of protein production. The difference between the hormone levels of pregnant mothers in noisy versus quiet areas increased as birth approached.
In a 2000 publication, a review of studies on birthweight and noise exposure note that while some older studies suggest that when women are exposed to >65 dB aircraft noise a small decrease in birth weight occurs, in a more recent study of 200 Taiwanese women including noise dosimetry measurements of individual noise exposure, the authors found no significant association between noise exposure and birth weight after adjusting for relevant confounders, e.g. social class, maternal weight gain during pregnancy, etc.
Cognitive development
When young children are regularly exposed to levels of noise that interfere with speech, they may develop speech or reading difficulties, because auditory processing functions are compromised. Children continue to develop their speech perception abilities until they reach their teens. Evidence has shown that when children learn in noisier classrooms, they have more difficulties understanding speech than those who learn in quieter settings.
In a study conducted by Cornell University in 1993, children exposed to noise in learning environments experienced trouble with word discrimination, as well as various cognitive developmental delays. In particular, the writing learning impairment dysgraphia is commonly associated with environmental stressors in the classroom.
High noise levels have also been known to damage the physical health of small children. Children from noisy residences often have a heart rate that is significantly higher (by 2 beats/min on average) than those of children from quieter homes.
Again sound affects us cognitively. How well you work is very dependent on the sound around you. Your kids may tell you that they do their homework much better with loud music playing. It’s not true unfortunately. The loud music is probably taking up critical audio bandwidth and they’re not able to hear that internal voice so well. They may do their homework for longer so you may get a better result, but they’re not doing more work per minute. The most distracting sound of all is the human voice. If somebody’s speaking next to you, it’s very difficult to block out that sound. We have no earlids and distracting human conversation hugely impedes your productivity.The final way sound affects us is behaviourally. We will tend to move away from unpleasant sounds if we can and even gravitate towards pleasant sounds. Sound can cause us stress and make us behave negatively. It makes us less sociable, less helpful and less approachable if we’re in a noisy setting.
Behaviourally
So sound changes us in powerful ways and those ways are running all the time. It’s important to know this because if you start to listen consciously to the sound around you, you could start to design your environment so that those effects are not working against you.
It becomes paramount to have a good sound system and make sure its settings sound soft and mild.
That’s why sound has measures (Decibel) and sound equipment are designed with decibel control meters.
Now, sound affects us physiologically in very powerful ways. Because hearing is your primary warning sense, a sudden sound will start a process. It releases cortisol, it increases your heart rate, it changes your breathing. This is because we’ve been programmed over hundreds of thousands of years to assume that any sudden or unexplained sound is a threat and your body gets ready to fight or flee. That happens to us an awful lot. Even though we may know that a bus letting off its air brakes or a car backfiring or somebody dropping a plate is not dangerous, it nevertheless puts us into that state. By the way, if you’ve got an alarm clock with a traditional bell, or even a beeper on it, a buzzer, any kind of sudden sound, please change it. It’s not good for you to wake up to that kind of sound.
Noise regulation
Environmental noise regulations usually specify a maximum outdoor noise level of 60 to 65 dB(A), while occupational safety organizations recommend that the maximum exposure to noise is 20 hours per week at 60 to 70 dB(A). For every additional 3 dB(A), the max.
Exposure time is reduced by a factor 2, e.g. 20 hours per week at 88 dB(A). Sometimes, a factor of two per additional 5 dB(A) is used, however, these occupational regulations are acknowledged by the health literature as inadequate to protect against hearing loss and other health effects. In an effort to prevent noise-induced hearing loss, many programs and initiatives have been created, like the Buy Quiet program, which encourages employers to purchase quieter tools and equipment, and the Safe-In-Sound Award, which recognizes organizations with successful hearing loss prevention strategies.
physiologically
Sound affects our bodies. Your body is 70% water. Sound travels well in water, so we’re very good conductors of sound. It’s not surprising that sound has a powerful effect on us. Hearing is your primary warning sense, just like every animal on the planet. Do you know there are no deaf vertebrates? There are plenty of vertebrates who don’t see very well at all or not at all, but the hearing is a universal sense, as Seth Horowitz calls it.
Now, sound affects us physiologically in very powerful ways. Because hearing is your primary warning sense, a sudden sound will start a process. It releases cortisol, it increases your heart rate, it changes your breathing. This is because we’ve been programmed over hundreds of thousands of years to assume that any sudden or unexplained sound is a threat and your body gets ready to fight or flee. That happens to us an awful lot. Even though we may know that a bus letting off its air brakes or a car backfiring or somebody dropping a plate is not dangerous, it nevertheless puts us into that state. By the way, if you’ve got an alarm clock with a traditional bell or even a beeper on it, a buzzer, any kind of sudden sound, please change it. It’s not good for you to wake up to that kind of sound.
With regard to indoor noise pollution in residences, the U.S. Environmental Protection Agency (EPA) has not set any restrictions on limits to the level of noise. Rather, it has provided a list of recommended levels in its Model Community Noise Control Ordinance, which was published in 1975. For instance, the recommended noise level for indoor residences is less than or equal to 45 .
Noise pollution control in residences is not funded by the federal government in part because of the disagreements in establishing causal links between sounds and health risks, since the effect of noise is often psychological and also, because it leaves no singular tangible trace of damage on the human body. For instance, hearing loss could be attributed to a variety of factors including age, rather than solely due to excessive exposure to noise. A state or local government is able to regulate indoor residential noise, such as when excessive noise from within a home causes disturbances to nearby residences.
Sound affects every aspect of our lives – even in our communication.
Cognitively
Thirdly, sound affects us cognitively. How well you work is very dependent on the sound around you. Your kids may tell you that they do their homework much better with loud music playing. It’s not true unfortunately. The loud music is probably taking up critical audio bandwidth and they’re not able to hear that internal voice so well. They may do their homework for longer so you may get a better result, but they’re not doing more work per minute. The most distracting sound of all is the human voice. If somebody’s speaking next to you, it’s very difficult to block out that sound. We have no ear lids and distracting human conversation hugely impedes your productivity.
Behaviourally
Sound can cause us stress and make us behave negatively. It makes us less sociable, less helpful and less approachable if we’re in a noisy setting.
So sound changes us in four powerful ways and those four ways are running all the time. It’s important to know this because if you start to listen consciously to the sound around you, you could start to design your environment so that those effects are not working against you.
Prevention
A hearing protection device (HPD) is an ear protection device worn in or over the ears while exposed to hazardous noise to help prevent noise-induced hearing loss. HPDs reduce (not eliminate) the level of the noise entering the ear. HPDs can also protect against other effects of noise exposure such as tinnitus and hyperacusis. Proper hygiene and care of HPDs may reduce chances of outer ear infections. There are many different types of HPDs available for use, including earmuffs, earplugs, electronic hearing protection devices, and semi-insert devices. One can measure the personal attenuation rating through a hearing protection fit-testing system or download a decibel meter app on your android phone.
Earmuff style hearing protection devices are designed to fit over the outer ear, or pinna. Earmuff HPDs typically consist of two ear cups and a headband. Earplug style hearing protection devices are designed to fit in the ear canal. Earplugs come in a variety of different subtypes. Electronic microphones, circuitry, and receivers perform active noise reduction, also known as noise-canceling, in which a signal that is 180-degrees out-of-phase of the noise is presented, which in theory cancels the noise. Canal caps are similar to earplugs in that they consist of a soft tip that is inserted into the opening of the ear canal.
Majorly, sound engineers should ensure they measure the level of sound frequency output in any event halls under their control.
Regulations
That’s why sound has measures (Decibel) and sound equipment are designed with decibel meters.
Wisdom is profitable to direct.  Let’s make our event halls sound system friendly.
Concluded.
With additional material from WHO.

By: Igbiki Benibo