Noise at the time of COVID 19: The impact in some areas in Rome and Milan, Italy

Abstract

The COVID-19 pandemic was confirmed in Italy at the end of January 2020, when the first positive cases for the virus were identified. At the beginning of March, the virus had spread to all Italian regions and on 10 March 2020 the lockdown phase began, limiting the movement of people and prohibiting almost all commercial activities, businesses and non-essential industries. As a result, millions of people were forced to stay at home, causing a drastic drop in traffic volume, which significantly changed the acoustic environment and air quality of cities. On 4 May 2020, the lockdown was partially lifted and activities were progressively reopened. Therefore, traffic gradually started to increase and, consequently, the noise emitted by motor vehicles. This behaviour was confirmed by the data collected by the DYNAMAP system, an automatic platform developed within the LIFE DYNAMAP project, providing real time traffic noise maps in terms of sound pressure levels and impacts at receivers (people and dwellings exposed to noise level bands). In this paper traffic and non-traffic-related noise events in the cities of Rome and Milan from March to May 2020 are analysed and compared to the corresponding values in 2019 to evaluate the effects of the lockdown period.

Quieted City Sounds during the COVID-19 Pandemic in Montreal

“…As with other cities, in addition to having variation across multiple sites, there were differences in the effects of lockdown on days, evening, and nighttime sound levels and across weekdays and weekends (see Section 2.2.5). However, in contrast to seeing more pronounced differences between day and night [11] or weekdays and weekends [10], Montreal's sites showed a flattening during lockdown between weekday and weekend distinctions and between day, evening, and night levels (as did [19]).…”

“…The time of the week was also important. A related study from the same Milan sensor network showed a 90% drop in traffic volume on Sundays compared to mean values between 50 and 70% on other days [10]. A separate study of five locations in Madrid showed that the reduction was unequal across times of day and for different urban morphologies, with markedly lower levels on weekends.…”

“…Measures of mean noise reductions for cities where such figures were reported were usually at least an order of magnitude (using usually L den or 24-h LA eq measurements): 2-3 dBA in Stockholm, Sweden [7]; 4-6 dBA in Lyon, France [8] and London, UK [9]; 6-8 dBA in Milan, Italy [10], and Paris, France [8]. The reductions also produced effects that could be measured in terms of populations, such as an Italian study showing that 60% fewer people were living at L den levels greater than 65 dB than had been living at these levels for previous years [10].…”

“…The aforementioned study of Monza, Italy [21] demonstrated how in the post-lockdown phase, levels rose from their lockdown minimum, but did not quite return to 2019 levels. In Rome and Milan, these levels were calculated as returning to 94% of the pre-lockdown sound levels [10]. In Stockholm, these levels went 0.5-2.0 dBA below normal as national restrictions were eased and holiday gatherings were taking place [7].…”

Methods for Noise Event Detection and Assessment of the Sonic Environment by the Harmonica Index

“…In 2020, a major change had occurred, due to severe restrictions on individual mobility issued by governments to tackle the COVID-19 pandemic. These restrictions have reshaped the acoustic environments in cities, and sources previously masked by road traffic noise have become audible to populations [7]. Notwithstanding the reduction of background noise levels, frequent occurrences of sound events have emerged, produced by different sources; including road vehicle passages, it is recognized that, for the same environmental conditions, human hearing is more sensitive to sound fluctuations over time rather than steady sounds (e.g., see [8]).…”