Hello everyone and welcome back to our blog! This post will be a continuation on noise pollution. In this post, we will be introducing to you some sources and effects of noise pollution before giving our definition.
Sources and types of noise pollution
Sources of noise pollution are primarily anthropogenic. However, this does not mean that natural sources cannot exist. Examples include animals and volcanic eruptions (Goines & Hagler, 2007). For example, the eruption of Krakatoa in 1883 produced a sound so loud it could be heard in Western Australia (OSU, n.d.). Estimates suggest that locals could experience hearing loss because of how loud the eruption was.
Anthropogenic sources of noise pollution include transportation, be it cars, trains or airplanes to household appliances, such as dishwashers and air-conditioners, or even broadcast systems, such as loudspeakers at clubs and concerts (Singh & Davar, 2004). Most concerning of all is that anthropogenic sources of noise pollution are often considered necessary (or a necessary consequence of life) (Goines & Hagler, 2007)
Apart from our environment where we live, our workplace environment is also important when we are looking at noise pollution. While we may be exposed to traffic noise daily at home, workers in the engineering and industrial sectors may be inundated with constant droning coming from machineries in their workplace (Singhal, Yadav, Hashmi, & Muzammil, 2009). Additionally, some workplace environments may require exposure to excessive loud noises such as drilling and boring in the construction industry. Constant exposure without proper mitigation can also lead to hearing loss (Koushki, Kartam, & Al-Mutairi, 2004).
Categories of noise pollution
As seen from the sources and types of noise pollution, we can also categorise these issues into categories, namely: loudness and pitch.
Firstly, noise can be loud or soft depending on the power level emitted by the source. As discussed above, workers in the construction industry are exposed to noise that can exceed 100 decibels (dB) (Koushki et al., 2004). Decibel is the unit of measurement for sound on a logarithmic scale, where every 10 dB increase is twice as loud as the previous. To illustrate what 100 dB is, imagine a motorcycle passing by in front of you (Zhang, 2016). As seen in the image, hearing damage begins when there is prolonged exposure to loud sounds above 80 dB. However, constant exposure to sound, even at low loudness can also be an issue. As many of us are aware, we are distracted by sounds when we are studying or focusing on our tasks at hand. While these sounds may not have a direct impact on hearing, indirect stressors may have a negative impact on our health. We will further discuss the effects of noise pollution below.
Secondly, the pitch of sound can also play a factor when considering noise pollution. As mentioned in our previous post, humans can hear between the frequency of 20 to 20,000 Hz. However, high pitched sounds such as the iPhone alarms or a fly buzzing would be more annoying than the music we listen to on the daily basis. Similarly, low pitched sounds such as trucks passing by or bass drums would be considerably annoying when constantly exposed. As Professor Taylor mentioned in his lecture, “tonal noises are more intrusive”, that is, sounds at a certain pitch without variation tends to become annoying.
Thus, while loudness can cause direct hearing damage or loss, constant exposure to sounds that are an annoyance, even at lower volumes and unnatural pitches (high or low) can also lead to significant negative implications to health.
Effects of noise pollution
While unable to directly cause mental problems, noise pollution can certainly increase your risks of catching one (Singh & Davar, 2004). Noise pollution is thought to elevate risks for many mental health problems, such as anxiety, emotional instability and psychosis (Stansfeld & Matheson, 2003).
Some obvious effects of noise pollution are hearing impairment and disturbed sleep. More interestingly, noise pollution can even lead to cardiovascular and mental issues (Goines & Hagler, 2007). Even in our sleep, our ears are constantly listening. Thus, noise pollution can lead to increased stressing of our body as our brain treats noise as a sign of danger. The constant triggering of the endocrine and autonomic nervous systems can lead to/or increase the risks of cardiovascular diseases (Stansfeld & Matheson, 2003).
When considering our environment, the effects of noise pollution can also be discussed. While SONAR (sound navigation ranging) is used as a tool underwater by submarines, these sounds can be likened to a “sound bomb” to marine ecosystems. Marine mammals such as whales and dolphins use sounds to communicate underwater, which can significantly alter their behaviours, leading to beaching events (Buck & Clavert, 2008). Furthermore, the implications of noise pollution on marine life is still not fully understood, which could surface more issues in the long run (Buck & Clavert, 2008). Similar to our post on land pollution, it would be prudent to adopt the precautionary principle rather than take reflexive actions after the damage has been done.
Our definition of noise pollution
Recognising the complexity of noise pollution, we decide to define it less strictly. Noise pollution means
“The anthropogenic emission of sound that leads to negative impacts on human and environmental health, regardless how it the sound is generated, its frequency and loudness”
This ensures that we can provide adequate mitigation not only to humans but also our environment. Although the definition is less strict as the effects of sound is not fully understood, it makes sense to err on the side of caution. As far as we know, the effects of exposure to noise, be it loud or constant, tends to lead to negative effects on health. In our next post, we will look at legislation governing the issue of noise pollution.
See you there!
Ryan
References
Buck, E. H., & Clavert, K. (2008). Active military sonar and marine mammals: events and references.
Goines, L., & Hagler, L. (2007). Noise pollution: a modem plague. South Med J, 100(3), 287-294.
Koushki, P., Kartam, N., & Al-Mutairi, N. (2004). Workers’ perceptions and awareness of noise pollution at construction sites in Kuwait. Civil Engineering and Environmental Systems, 21(2), 127-136.
OSU. (n.d.). Historial Eruption Sounds. OSU. Retrieved from http://volcano.oregonstate.edu/historical-eruption-sounds
Singh, N., & Davar, S. C. (2004). Noise pollution-sources, effects and control. Journal of Human Ecology, 16(3), 181-187.
Singhal, S., Yadav, B., Hashmi, S., & Muzammil, M. (2009). Effects of workplace noise on blood pressure and heart rate.
Stansfeld, S. A., & Matheson, M. P. (2003). Noise pollution: non-auditory effects on health. British medical bulletin, 68(1), 243-257.
Zhang, X. (2016). Noise Prediction of a NACA 0015 Airfoil with Gurney Flap: A study based on Time-Resolved Particle Image Velocimetry.