In the fall of this year, all-electric buses were introduced on Gothenburg’s bus route 60. The implementation was spearheaded by the ElectriCity initiative, which brought together representatives from industry, research, and government agencies to achieve sustainable urban mobility.
The road on this bus route is significantly uneven in several locations. The previous bus system was chastised for producing considerable noise, which was especially audible in hilly areas. Low-frequency noise in indoor spaces was found to be a source of disturbance in the residential neighbourhood in previous noise assessments.
The quantity of noise that electric bus travel would produce, as well as the extent to which it would be hazardous to people’s health, were unknown. Low-frequency noise was discovered to be especially important since it has a great potential for generating disturbance and is absorbed more slowly by façades or noise barriers than higher-frequency noise.
Low-frequency noise has a bad rep for being hard to get rid of.
We can be disturbed by a wide range of noises, but low-frequency noise is particularly problematic since it is filtered less effectively by facades or windows, allowing it to enter dwellings more easily. Even the tiniest changes in its amount have an immediate impact according to Kerstin Persson Waye, Professor of Environmental Medicine at Sahlgrenska Academy, University of Gothenburg.
The researchers performed two sets of interviews with randomly selected residents prior to and during the conversion to electric buses. In two city districts, Masthugget and Lunden, one-fifth of the population lived in homes along the bus route. The remaining half of the volunteers, who lived a long distance away, formed the reference group.
Noise measurements were taken simultaneously in a large number of homes, including indoors, which had not previously been measured. In order to obtain valid and representative data on low-frequency noise, these investigations necessitated the use of specialised equipment with ten to twelve microphones in each dwelling unit.
Between the first and second stages of the trial, there were clear and statistically significant differences. They were applied to fluctuations in sound levels, particularly in low frequencies, as seen by residents, as well as reports of noise discomfort from neighbours. The proportion of respondents who reported hearing bus noise declined from 75% to 39%, and the proportion who reported being significantly disturbed by noise decreased from 26% to 5%.
There is a visible improvement in health status.
In addition, the reported health repercussions of the intervention were significantly reduced. The number of people who said they were tired once or twice a week decreased from 49 to 39 percent in the trial, bringing it closer to the control group. The percentage of people who said they were extremely weary during the day dropped from 22% to 17%, while the percentage of people who said they were in a bad mood dropped from 22% to 17%.
As a result, there was an improvement: participants said they felt much better. The findings may be applicable to residential circumstances in which bus commuting accounts for a significant portion of exposure, but cannot be guaranteed to represent the entire population or that the positive health benefits would last longer term.
According to an additional study, as other modes of urban transportation become more silent, it may have an influence on public health.
The survey gathered 1,326 respondents in Phase 1 (with a response rate of 34%) from June to September 2019 and 1,191 respondents in Phase 2 (with a response rate of 34%) from June to September the following year (response rate: 36 per cent). The response rate was roughly in line with expectations.
Follow-up research was undertaken in the group of those who did not reply, using a reduced questionnaire, to determine whether they differed from those who did respond. Despite the fact that those who elected not to participate in the entire poll had a lower level of education and a smaller number of homeowners than those who participated, there were no statistically significant variations in perceptions of the noiseiness.
Story Source: Original story written by the University of Gothenburg. Note: Content may be edited for style and length by Scible News.
