Standardized noise annoyance scales in Chinese, Korean and Vietnamese

Internationally standardized annoyance scales are required in order to compare community responses to environmental noises measured in various linguistic regions. ICBEN Team 6 organized an international joint study to establish standardized noise annoyance scales and has developed scales and questions in nine linguistic regions. With the exception of Japan, all of these regions were Euro-American. Thus, it has been necessary to augment the original ICBEN study by utilizing the ICBEN method to construct noise annoyance scales for use in other Asian countries, because noise pollution is becoming an increasingly important environmental issue in these countries. Also, Asian data should be compared internationally with Euro-American data. The present study reports on the use of the ICBEN method to construct annoyance scales in Chinese, Korean and Vietnamese.     

CURRENT RESEARCH TOPICS AND PROBLEMS: THE ROLE OF ICBEN

The structure and work of the International Commission on Biological Effects of Noise (ICBEN) are briefly presented. The current and future priorities of ICBEN Noise Team 6 “Community Response to Noise” are discussed in detail. These priorities comprise studies of good sound environments and assessment methods for noise annoyance in multi-source environments.     

Vibration in dwellings from road and rail traffic — Part III: towards a common methodology for socio-vibrational surveys

While a range of international standards defining noise, vibration and other physical environmental measures have been established, common methodologies for measuring people's reactions to these same environmental effects are still in their infancy. This reduces the comparability of prevalence statistics and exposure-effect relationships developed by different researchers. The public authorities are served incompatible or seemingly conflicting information from different surveys when deciding on appropriate guidelines and limits. Drawing on experiences with the 1998 Norwegian Socio-vibrational Survey and a Swedish socio-acoustic survey supplemented with vibration measures, a new Nordtest Method: NT ACOU 106 Acoustics—Assessment of annoyance by vibrations in dwellings from road and rail traffic has been defined. The method describes sampling requirements, and proposes a mandatory verbal 5-point categorical annoyance scale and an optional 11-point numerical annoyance scale, both with lower anchoring point “Do not notice”. A survey data output format is specified to allow researchers to pool data from different surveys.     

Context sensitive noise impact mapping

Apartments that are exposed to the same level of road traffic noise on front of the most exposed façade often have very different neighbourhood soundscapes. In the first part of this paper, a neighbourhood soundscape adjusted exposure indicator, NAL_den, is derived. NAL_den-values are designed to be used as input to traditional exposure-effect relationships to improve annoyance impact estimates. In the second part, generic spatial procedures are developed and implemented. These produce map presentations in the form of contiguous neighbourhood quality areas. The quality of each neighbourhood is determined from the predicted annoyance impacts for residents. Noise impact maps provide experts, politicians, and the public with high-level impact visualizations of condensed status, “what-if” and scenario information. Results and illustrations are based on data from the Norwegian socio-environmental survey database, and a comprehensive national noise mapping effort. The methodology should work well for mapping Europe’s “black” and “grey” areas.     

General scales of community reaction to noise (dissatisfaction and perceived affectedness) are more reliable than scales of annoyance

General measures of reaction to noise, which assess the respondent's perceived affectedness or dissatisfaction, appear to be more valid and internally consistent than more narrow measures, such as specific assessment of noise annoyance. However, the test-retest reliability of general and specific measures has yet to be compared. As a part of the large-scale Sydney Airport Health Study, 97 respondents participated in the same interview twice, several weeks apart. Test-retest reliabilities were found to be significant (p < 0.001) for two general questions and three specific "annoyance" questions. The general measures were significantly more valid for four of the six correlations (with activity disturbance), and more stable than the annoyance scales for five of the six possible test-retest comparisons. Amongst 1,015 respondents at Time 1, the questions regarding general reaction were more internally consistent than the questions regarding annoyance. Taken together, these data indicate that general measures of reaction to noise have superior psychometric properties (validity, internal consistency, and stability) compared with measures of specific reactions such as annoyance.     

Individual differences in noise annoyance and the uncomfortable loudness level

Uncomfortable loudness levels were measured for two groups of subjects with either high or low scores on a noise annoyance questionnaire. The study was conducted in two stages. In the first stage scores of noise annoyance, general annoyance and locus of control were obtained from 122 respondents. Two groups of responders on the noise annoyance questionnaire attended the laboratory for the second stage involving a determination of the uncomfortable loudness level (ULL) by two methods (Békésy and analogue adjustment) and for two types of sound source (white noise and a 1 kHz tone). The key findings from the first stage were that (i) noise annoyance scores were not bimodal, showing no significant deviation from normality, (ii) females showed higher noise annoyance and (iii) both general annoyance and locus of control scales showed significant positive correlations with noise annoyance. Findings from the second stage showed that (i) Békésy determinations gave higher ULL's than those from the analogue adjustment method, (ii) based on annoyance scores, noise-annoyed subjects produced significantly higher ULL's than their less annoyed counterparts but only with the analogue determination with a 1 kHz tone, (iii) females produced markedly lower ULL's than males and (iv) deactivation, locus of control and extroversion were identified as mediating factors in the setting of the ULL. The results were further discussed in terms of methodological differences between this and earlier studies.     

An experiment on auditory and non-auditory disturbances caused by railway and road traffic noises in outdoor conditions

In a laboratory experiment, disturbance caused by two types of noise (railway and road traffic noises) at three noise levels (55, 65 and ) in two kinds of stimulation conditions (listening and calculation) was investigated. Thirty Japanese and thirty Chinese subjects performed a listening or calculation task while each noise was presented for 6 min. The subjects assessed the disturbance of their activities using 5-point verbal scales constructed by ICBEN method. A railway bonus, mainly caused by noise masking, was found in the listening task but not in the calculation task. There was a significant difference between the effects of two noises on listening performance when noise level was 75 dB, but no difference was found between railway and road traffic noises on task performance. The results suggest that the disturbance evaluation is determined by several factors and that the interaction among the factors increases with the increase of noise level. Evaluation disturbance is not related to task performance in certain cases.     

Community noise survey of the city of Valdivia, Chile

A noise map of the city of Valdivia is created as a way to evaluate the noise of the city. This is a process that is usually associated with high operative costs. Some statistical techniques have been employed that have allowed the extrapolation of some measured values to assess noise at different times of the year, including “off” days thus reducing time and costs. The day-evening-night level L_DEN is used as the rating method to describe long-term annoyance. In conclusion, the noise pollution in the city is widespread throughout most of its streets area, where measured noise values are similar to those commonly observed in cities that do not have mitigation programs and whose road traffic is their principal noise generation source.     

A -WEIGHTED EQUIVALENT SOUND LEVEL AS A PREDICTOR OF THE ANNOYANCE CAUSED BY ROAD TRAFFIC CONSISTING OF VARIOUS PROPORTIONS OF LIGHT AND HEAVY VEHICLES

A laboratory study was conducted to examine the relationship between noise annoyance and the proportion of heavy vehicles in a mixture of trucks and passenger cars. Twenty normal-hearing subjects were asked to judge the annoyance caused by the sounds from a continuous stream of vehicles, assuming they were exposed to it at home on a regular basis. The number of passby events as well as the A- weighted equivalent sound level were kept constant. Results showed that in such conditions, the annoyance is virtually independent of the proportion of heavy vehicles.     

Easing the concept “Balanced Approach” to airports with densely busy surroundings – The case of Congonhas Airport

This paper presents the difficulties found in trying to apply the “Balanced Approach” concept of ICAO (UN-International Civil Aviation Organization) on the noise pollution mitigation at urban Brazilian airports using, as a case study, the Congonhas Airport. It has been discussed by means of alternative operating scenarios, how to make the concept more flexible, aiming to bring the benefit of any additional acoustic comfort, without diminishing the installed capacity and already limited for environmental reasons. The results show that there are conditions for improvement, since there are both awareness of all players involved and permanent and real-time noise monitoring, even if those mitigating measures are not reflected on the noise annoyance models currently adopted for the land use planning.     

Individual differences in sensitivity to traffic noise: An empirical study

Repeated interview surveys were made in surburban residential areas of London and Liverpool. In both cities two sites were selected according to the noise exposure level (70 or 80 dB(A) 18 hour L₁₀, 1 metre from dwelling facade). The characteristics of the neighbourhoods were similar in all other relevant respects. The initial sample size obtained was 413 which was reduced by 21% when the interviews were repeated. Questions included noise dissatisfaction semantic differential scales, sensitivity to noise scales, environmental sensitivity scales, and classificatory questions. Two smaller random samples of 25 respondents selected from each of the noisy sites were also given two personality tests. It was found that (a) there was no evidence to suggest that the noise annoyance distributions were not normal—more specifically, they did not appear to be bimodal; (b) retest correlation coefficients were low but significant, indicating acceptable reliability of the noise dissatisfaction scale; (c) the reliability of the self-rating noise sensitivity scale was also found to be low but significant; (d) no personality factor was found to relate to annoyance or sensitivity to noise in a consistent manner. A general conclusion drawn was that noise dissatisfaction variation is due more to randomness in response to the measuring instrument than to individual differences in sensitivity to noise.     

Sleep disturbance caused by meaningful sounds and the effect of background noise

To study noise-induced sleep disturbance, a new procedure called “noise interrupted method”has been developed. The experiment is conducted in the bedroom of the house of each subject. The sounds are reproduced with a mini-disk player which has an automatic reverse function. If the sound is disturbing and subjects cannot sleep, they are allowed to switch off the sound 1 h after they start to try to sleep. This switch off (noise interrupted behavior) is an important index of sleep disturbance. Next morning they fill in a questionnaire in which quality of sleep, disturbance of sounds, the time when they switched off the sound, etc. are asked. The results showed a good relationship between L_Aeq and the percentages of the subjects who could not sleep in an hour and between L_Aeq and the disturbance reported in the questionnaire. This suggests that this method is a useful tool to measure the sleep disturbance caused by noise under well-controlled conditions.     

Relationship between loudness perception and noise indices in Valdivia, Chile

Residents perception of road traffic noise loudness in relation to the measured noise indices close to their dwellings was studied. Percentile distributions of five loudness categories as a function of the Day-Night noise index L_DN were obtained. Hearing sensitivity was considered as a factor in loudness perception. In addition, the prevalence of people’s perception of traffic noise in the “Extremely Loud” loudness category was compared with percentage of people stating that they were “Highly Annoyed” by noise. It is concluded that hearing sensitivity for noise is one of the variables that explains the loudness classification difference in different L_DN index ranges and that the percentages of people “Highly Annoyed” by noise are slightly higher than the percentages obtained in the “Extremely Loud” category of loudness perception.     

A GIS based road traffic noise prediction model

A road traffic noise prediction model has been developed suitable for use in China. This model is based on local environmental standards, vehicle types and traffic conditions. The model was accurate to 0.8 dBA at locations near the road carriage way and 2.1 dBA within the housing estate, which is comparable to the FHWA model. An integrated noise-GIS system was developed to provide general functions for noise modeling and an additional tool for noise design, where a new interaction mode in “WHAT IF Question/Explanation” format was used. Application of this system offered improvements in the efficiency and accuracy of traffic noise assessment and noise design.     

Community responses to road traffic noise in Hanoi and Ho Chi Minh City

Vietnam is a developing country in southeast Asia, and its environment has been seriously affected by industrialization and urbanization. In large cities like Hanoi (northern Vietnam) and Ho Chi Minh City (southern Vietnam), noise emission from road traffic has been found to be a serious concern among general public. In 2005 and 2007, two large-scale socio-acoustic surveys of community response to road traffic noise were conducted to investigate human reactions to road traffic noise in these cities; the sample sizes were 1503 people in Hanoi and 1471 in Ho Chi Minh City. The noise exposure levels (L_den) were 70–83 dB in Hanoi and 75–83 dB in Ho Chi Minh City. Noise annoyance was estimated using standardized annoyance scales. For both cities, dose–response relationships were established between L_den and the percentage of highly annoyed respondents. Compared to annoyance responses of European people, Vietnamese were less annoyed by road traffic noise by about 5 dB. Hanoi respondents seemed to be more annoyed by noise than Ho Chi Minh City respondents. Conversation and sleep disturbances were not as serious as expected in either city. Furthermore, window orientation in the home was found to affect activity disturbances.     

Language specificity in the perception of voiceless sibilant fricatives in Japanese and English: implications for cross-language differences in speech-sound development

Both English and Japanese have two voiceless sibilant fricatives, an anterior fricative /s/ contrasting with a more posterior fricative /∫/. When children acquire sibilant fricatives, English children typically substitute [s] for /∫/, whereas Japanese children typically substitute [∫] for /s/. This study examined English- and Japanese-speaking adults' perception of children's productions of voiceless sibilant fricatives to investigate whether the apparent asymmetry in the acquisition of voiceless sibilant fricatives reported previously in the two languages was due in part to how adults perceive children's speech. The results of this study show that adult speakers of English and Japanese weighed acoustic parameters differently when identifying fricatives produced by children and that these differences explain, in part, the apparent cross-language asymmetry in fricative acquisition. This study shows that generalizations about universal and language-specific patterns in speech-sound development cannot be determined without considering all sources of variation including speech perception.