Survey context and question wording affects self reported annoyance due to road traffic noise: a comparison between two cross-sectional studies

<p>Abstract</p> <p>Background</p> <p>Surveys are a common way to measure annoyance due to road traffic noise, but the method has some draw-backs. Survey context, question wording and answer alternatives could affect participation and answers and could have implications when comparing studies and/or performing pooled analyses. The aim of this study was to investigate the difference in annoyance reporting due to road traffic noise in two types of surveys of which one was introduced broadly and the other with the clearly stated aim of investigating noise and health.</p> <p>Methods</p> <p>Data was collected from two surveys carried out in the municipality of Malmö, southern Sweden in 2007 and 2008 (n = 2612 and n = 3810). The first survey stated an aim of investigating residential environmental exposure, especially noise and health. The second survey was a broad public health survey stating a broader aim. The two surveys had comparable questions regarding noise annoyance, although one used a 5-point scale and the other a 4-point scale. We used geographic information systems (GIS) to assess the average road and railway noise (L_Aeq,24h) at the participants' residential address. Logistic regression was used to calculate odds ratios for annoyance in relation to noise exposure.</p> <p>Results</p> <p>Annoyance at least once a week due to road traffic noise was significantly more prevalent in the survey investigating environment and health compared to the public health survey at levels > 45 dB(A), but not at lower exposure levels. However no differences in annoyance were found when comparing the extreme alternatives "never" and "every day". In the study investigating environment and health, "Noise sensitive" persons were more likely to readily respond to the survey and were more annoyed by road traffic noise compared to the other participants in that survey.</p> <p>Conclusions</p> <p>The differences in annoyance reporting between the two surveys were mainly due to different scales, suggesting that extreme alternatives are to prefer before dichotomization when comparing results between the two. Although some findings suggested that noise-sensitive individuals were more likely to respond to the survey investigating noise and health, we could not find convincing evidence that contextual differences affected either answers or participation.</p

Attractive "Quiet" Courtyards: A Potential Modifier of Urban Residents' Responses to Road Traffic Noise?

The present paper explores the influence of the physical environmental qualities of “quiet” courtyards (degree of naturalness and utilization) on residents’ noise responses. A questionnaire study was conducted in urban residential areas with road-traffic noise exposure between LAeq,24h 58 to 68 dB at the most exposed façade. The dwellings had “quiet” indoor section/s and faced a “quiet” outdoor courtyard (LAeq,24h &amp;lt; 48 dB façade reflex included). Data were collected from 385 residents and four groups were formed based on sound-level categories (58–62 and 63–68 dB) and classification of the “quiet” courtyards into groups with low and high physical environmental quality. At both sound-level categories, the results indicate that access to high-quality “quiet” courtyards is associated with less noise annoyance and noise-disturbed outdoor activities among the residents. Compared to low-quality “quiet” courtyards, high-quality courtyards can function as an attractive restorative environment providing residents with a positive soundscape, opportunities for rest, relaxation and play as well as social relations that potentially reduce the adverse effects of noise. However, access to quietness and a high-quality courtyard can only compensate partly for high sound levels at façades facing the streets, thus, 16% and 29% were still noise annoyed at 58–62 and 63–68 dB, respectively. Implications of the “quiet”-side concept are discussed

Combined effects of noise and vibration from train and road traffic

The research project addresses three aims. The first is whether a \u93train bonus\u94 can be expected, i.e. whether noise from railway traffic is perceived as less annoying than road traffic noise and the same level. The second aim is to investigate the connection between disturbance and exposure to simultaneous noise and vibration from train traffic. The third issue is to investigate concurrent effects from simultaneous exposure to noise from train and road traffic

A system for railway noise sleep disturbance trials

In Sweden a new research project aimed at studying noise and vibration from railway traffic has been started. An important part of the project is controlled laboratory experiments where subjects are exposed to noise and vibration when sleeping. The first set of experiments (using only noise) have already started, and the vibration excitation is under construction. Here the focus is on the construction of the laboratory and the design of the experiments, but some preliminary results are also presented. The sound system consists of roof mounted speakers for low frequencies, and two speaker cabinets for the high frequency part. Train passages recorded in the field on the façade of a building are filtered to account for façade insulation and presented to the subjects. This enables many scenarios to be studied with the same setup by selecting the individual sounds and changing the parameters of the filter. The vibration excitation system under construction will be based on electro-dynamical shakers which will interact with the bed to force it to vibrate

Noise and vibration generation for laboratory studies on sleep disturbance

The research project TVANE is aimed at studying the effects of noise and building vibrations from railway traffic, and is sponsored by the Swedish railway infrastructure manager Banverket. The project includes many studies performed both in the field with questionnaires and noise and vibration measurements, and in the laboratory. This paper describes the design of a low cost vibrating bed used in laboratory sleeping experiments, and also the sound and vibration signals that the subjects were exposed to

Effects of railway noise and vibrations on sleep : experimental studies within the Swedish research program TVANE

This paper describes a laboratory sleep study with an exposure situation corresponding to a dwelling close to a railway. Both noise and bed vibrations were generated for passing trains, and the sleep quality of the test subjects was evaluated using questionnaires before and after sleep. A total of 21 test subjects slept five nights in the laboratory, and three different exposure situations were presented in a randomized order after two nights for habituation. The three exposures were combined from two noise levels and two vibration amplitudes; one with high noise levels and strong vibrations, one with lower noise levels and strong vibrations and one with high noise levels and weaker vibrations. The results indicate that the perceived sleep disturbance from noise increased with increasing vibration amplitude. There was no such interaction effect for perceived sleep disturbance due to vibrations, i.e. sleep disturbance due to vibrations was the same irrespective of noise level. These results suggest that it will not be sufficient to reduce the noise levels to protect from sleep disturbances, e.g. by sound insulating windows and noise barriers, if vibration levels are high. The vibration levels must also be addressed