1. Introduction
Noise is usually defined as unwanted or undesired sound judged to be unpleasant, loud or disruptive to hearing. Environmental noise is the accumulation of all noise present in a specified environment. Environmental Noise can also be defined as an unwanted or harmful outdoor sound created by human activity, such as noise emitted by means of transport, road traffic, rail traffic, air traffic and industrial activity (Environmental Noise pollution, 2014). A study on environmental noise pollution in Nigeria urban centers found that increase in population, commercial activities and road traffic volume, increase the level of noise generation. Other concomitant noises have been noted to be severe in rapidly expanding cities, towns and regions in Nigeria as observed in the South Eastern States (Onuu, 1992). Many studies on noise pollution have been conducted (Chibuike et al. 2018; Pretzsch et al. 2015; Wang et al. 2014; Baloye and Palamuleni, 2015).
Oyedepo et al. (2018) produced dataset to assess the noise pollution levels in Ota Metropolis and discovered that only 2 out of the 41 locations considered are under normally acceptable situation while the noise levels of other areas are not acceptable.
Noise exposure is not a new phenomenon. Records show that even in medieval times, carriages and horseback riding were banned during the night in some cities in Europe, in order to prevent sleep disturbance (World Health Organization, 2000). Noise Pollution also known as sound pollution, is the propagation of noise with harmful impact on the activity of human or animal life. The source of outdoor noise worldwide is mainly caused by machines, transport, and propagation systems (Wikipedia, 2016). Noise pollution can damage physiological health problems to people who are continuously subjected to it. In 1999, the World Health Organization (WHO) issued suggested community noise guidelines. It considered various environments noise levels, and noise impacts. In outdoor living areas (backyards, for example), a noise level of 50-55 dB(A) averaged over the daytime is considered moderately to seriously annoying; levels above 45d dB(A) averaged over nighttime hours can disturb sleep; and indoor noise levels above 35 dB(A) impact communication in a school.
Braj and Jain (1995) and Schwartz (2011), describe noise as air pollutant, which differs from other pollutants in the sense that it is transient in nature, and it is not a continuing or persisting phenomenon. Once the noise pollution stops, the environment becomes free of its effects. Garg (2010) expands this concept when he noted that noise is any unwanted sound that is not necessarily random. He noted that noise, particularly loud ones disturb people or make it difficult
for people to hear, and that conversations of other people may also be described as noise by people not involved. He added that any unwanted sound, such as barking of domesticated dogs, neighbors playing loud music, port mechanical saws, road traffic sounds which have now become a part of the urban culture, qualify as noise pollution.
The problem with noise is not only that it is unwanted, but also that it negatively affects human life and well-being. High noise levels can contribute to cardiovascular effects in humans and an increased incidence of coronary artery disease. While the elderly may have cardiac problems due to noise, according to World Health Organization, children are especially vulnerable to noise and the effects that noise has on children may be permanent. Noise poses a serious threat to a child’s physical and physiological health and may negatively interfere with a child’s learning and behavior (Wikipedia, 2006). Noise is a growing health threat, and if left unchecked, could result to hazardous conditions (Adejobi, 2012).
In considering the adverse effects of noise and the need for control, it is suggested by (Kaushik and Kaushik, 2008) that noise can be controlled by reduction in sources; use of sound absorbing silencers; planting of more trees with broad leaves; and legislation. Noise pollution from commercial areas and other urban factors can be mitigated by applying an important factor which is a computer model like ArcGIS (Karthik et.al., 2015). ArcGIS provides good visualization tools of noise propagation and assist in building a spatial decision support system that can be used for decision making