In recent years, the measurement of stress hormones including adrenaline, noradrenaline and cortisol has been widely used to study the possible increase in cardiovascular risk of noise exposed subjects. Since endocrine changes manifesting in physiological disorders come first in the chain of cause-effect for perceived noise stress, noise effects in stress hormones may therefore be detected in populations after relatively short periods of noise exposure. This makes stress hormones a useful stress indicator, but regarding a risk assessment, the interpretation of endocrine noise effects is often a qualitative one rather than a quantitative one. Stress hormones can be used in noise studies to study mechanisms of physiological reactions to noise and to identify vulnerable groups. A review is given about findings in stress hormones from laboratory, occupational and environmental studies.

This retrospective study presents the findings of inner ear damage documented in 53 children exposed to impulsive sound emitted by toy weapons and firecrackers. There were 49 boys and four girls aged between four and fourteen years. Thirty-nine children were affected unilaterally while fourteen had bilateral hearing loss (total of 67 ears). Most of the hearing loss (>70%) was sensorineural high frequency hearing loss, while only nine out of the 67 injured ears had sensorineural mid frequency hearing loss. Seven children sustained a traumatic ear drum perforation. Dizziness or tinnitus was reported by twenty children, with pathological ENG findings in four of them. This paper re-emphasizes the possibility of inner ear damage in children from exposure to noisy toys.

In 1999 a new I-INCE Technical Study Group TSG 2 was formed on "Noise labels for consumer and industrial products". This was intended to survey current methods for labelling and otherwise characterizing the noise emissions of consumer and industrial products. Note that labelling can mean more than just a physical label - it might be details in a Technical Manual. The measurement methods used by testing authorities were to be included in the survey. The methodologies were to be compared, and an assessment made of their relative effectiveness. The study of noise labelling is part of an educational program to advise on how, and in what form such labelling should be implemented. There has been active participation in the TSG from UK, USA, Japan, Norway, Turkey, Belgium and Brazil, with email exchange of information and 3 meetings, at Internoise 2000 in Nice, 2001 in Den Haag and 2002 in Dearborn, USA. More recently the survey questionnaire has been sent to all the 46 Member Societies of I-INCE. This paper explains the survey and summarises current results¹.

Noise is a health risk. The only scientifically established adverse health effect of noise is noise­induced hearing loss (NIHL). Besides noise may affect quality of life and cause annoyance and sleep disturbance. The present scientific evidence of potential non-auditory effects of noise on health is quite weak. Whether health promotion works in relation to noise may be reflected by permanent hearing threshold shift development in population studies. Hearing impairment continues to be the most prevalent disability in Western societies. The National Institute of Occupational Safety and Health (NIOSH) still rates noise induced hearing loss among the top ten work-related problems. Recent studies report that employees continue to develop noise induced hearing loss although to a lesser extent than before, in spite of occupational hearing conservation programmes. Besides socio-acusis and leisure noise seem to be an increasing hazard to hearing, also in young children and adolescents. This seems partly related to acute leisure noise exposure (e.g. toy pistols, amplified music). However, population studies increasingly find non­normal high-frequency hearing including the characteristic NIHL-"notch" around 6kHz also in subjects who do not report noise exposure incidents or activities. Today 12.5% of US children 6-19 years show a noise-"notch" in one or both ears (n= 5249, Niskar et al 2001). A Norwegian county audiometry survey on adults > 20 years (n=51.975) showed mean unscreened thresholds +10dB at 6kHz for both genders even for the youngest age group 20-24 years (Borchgrevink et al 2001). Accordingly, the present health promotion initiatives seem insufficient in relation to noise and noise-induced hearing loss.

In the United Kingdom, before the introduction of the various town and country planning acts and associated regulations, landowners were free to use their land in any way they wished, subject only to limitations imposed by lease or covenant and the avoidance of nuisance or trespass against neighbours. Any disputes arising would be resolved by negotiation or via a court of law. Under current planning laws and regulations, local authorities are empowered to impose special conditions or even to refuse development to prevent excessive nuisance, but the resulting noise management solutions are not always optimum from either the noise maker's or the noise exposed's points of view. In addition, the planning system has almost no effect on existing noise. Public inquiries provide a useful mechanism for the investigation of appeals against local authority decisions, or where the government has decided that issues of strategic or national importance need to be fully explored in a public forum. In practice, and largely because of individual disagreement, public inquiries can result in excessive delays while all interested parties are allowed to have their say. There seems to be an increasing consensus that the general inadequacy of existing methods of assessing noise impact is at least partly to blame. The new European Environmental Noise Directive represents a step change towards the imposition of one-size-fits-all regulatory or administrative procedures which should eventually contribute towards the reduction of public inquiry delays, but on the other hand, any weakening of the general principle of basing decisions on 'informed flexibility' will probably have significant negative consequences over the longer term.

The British Government earlier this year undertook a consultation on its proposal, announced in the Rural White Paper, to develop an Ambient Noise Strategy in England. The proposals envisage a three phase approach: In phase 1 we would aim to establish three key sets of information: • information on the ambient noise climate in the country - i.e. the number of people affected by different levels of noise, the source of that noise (road, rail, airports and industry) and the location of the people affected, by producing noise maps of the main sources of noise; •methods which the Government might use to assess the effects of noise - particularly regarding people's quality of life and tranquillity; • the techniques available to take action to improve the situation where bad or preserve it where good. In phase 2 we would aim to evaluate and identify options for prioritising the various alternatives from phase 1 in terms not only of costs and benefits but also time-scales and synergies and conflicts with other Government priorities including economic and social issues. An optimal policy reduces noise at lowest net cost, whilst capturing as many synergistic benefits, and minimising any potentially adverse impacts. Decision makers need to ensure that the impacts of the noise policies do not cost society more than the benefits expected. A recent study undertaken by the Government, looked at how a cost-benefit type framework could be used, with noise maps, to help inform such decisions. Finally, in phase 3, the Government would need to agree on the necessary policies to move towards the desired outcome - i.e. the National Ambient Noise Strategy itself. The results of the consultation are expected to be published later this year.

This paper considers the opportunities for noise control within the route corridor required for construction of road, rail and other guided transport schemes. It deals with control of noise generation at source, and in the transmission path close to the point of generation. In this way it is possible to control the amount of acoustic power generated, and to absorb part of the radiated power at points of reflection. Purely reflective wayside barriers do little to absorb acoustic energy, merely reflecting it in a different direction. Whilst this has selfish benefits to the receptor in the shadow zone of the barrier, it makes things worse for others on the reflective side of the geometry. The paper therefore considers the options available to the engineer in the design of rolling and sliding interfaces and the use of acoustically absorptive finishes on all surfaces close to the point of noise generation. This includes the running surface itself, structural components, retaining walls, over and under passes, and the inner surfaces of track and wayside barriers.

Ear muffs and ear plugs are widely used in the workplace to provide hearing protection for employees exposed to high levels of noise. Through an examination of the use of ear protectors in the workplace this paper explores the extent to which these devices can play a similar role in protecting members of the public from hearing damage arising from exposure to high levels of noise from leisure activities. It is concluded that the major limitation to the effective use of ear protectors for leisure use is likely to be the lack of easily accessible information, advice and guidance on the nature of the hearing protection risk from noisy leisure activities, and on the availability, selection and use of protectors, and of the need for regular hearing checks.

The term "noise sensitivity" is frequently used in many areas of noise research. However, it can be used to describe several different effects and it can be measured in different ways. In noise surveys, noise sensitivity refers to the fact that individuals differ in the annoyance produced by different sources of noise. Noise sensitivity can be viewed as an independent variable, which may be directly related to outcomes such as health status, or it can be conceptualized as a factor that modifies or mediates the effects of noise exposure on the outcome measure. Noise sensitivity is highly correlated with the general trait negative affectivity, a measure of the extent to which individuals perceive or report negative features of their environment or self. Indeed, few studies have demonstrated effects of noise sensitivity that are independent of negative affectivity. This implies that it is most appropriate to examine general indicators of reported sensitivity rather than a noise-specific measure. Noise sensitivity can also be considered in terms of physiological reactivity to noise sources. Such effects are often only weakly associated with self-reports of noise sensitivity. Habituation to noise is also an important topic to consider and again this appears to be largely independent of self-reported noise sensitivity. Overall, it would appear that it is important to distinguish between subjective reports of noise sensitivity and objective indicators. Different factors will modify these two aspects of noise sensitivity and this implies that different strategies are needed to influence them. Such effects must be taken into consideration when one considers whether control should be targeted at the community in general, or whether it should also cover the most sensitive individuals.