Noise attenuation against military noises has been measured in several cases under practical field conditions. Commercial and military versions of earmuff noise attenuation were measured against rifle noise. All the tested earmuffs attenuated the C-weighted peak level to less than 135 dB, which is less than the proposed recommendation value. Combat and shooting exercises create a risk of hearing damage, reaching a peak level of 180 dB. Measurements were done during attack exercises with blank and normal cartridges and during a defence exercise with normal cartridges. The noise exposure levels were relatively moderate (outside the ear 95­97 dB, in ear canal 82-85 dB) for military exercises. Peak levels of 110-120 dB for military trainers were measured in the ear canal during the conscript use of small-bore weapons. Combat vehicles and tanks are noisy, and for noise control during their use headgear with communication properties is worn. Noise inside such headgear was found to reach up to 120 dB, and the noise doses varied between 90 and 105 dB. Noise was also measured for aviation pilots in Finnish jet fighters. The cockpit values averaged 96 dB - 100 dB over the flight, whereas noise in the ear canal averaged 88 dB - 95 dB. The analyses indicated that radio noise is 4-10 dB higher inside the helmet than the background noise is, when measured as equivalent noise. The technicians on the ground were exposed to noise levels varying from 93 to 97 dB over the day. In practice, hearing protectors attenuate noise by 10-30 dB, depending on the frequency content of the noise sources. However, the difference when measured outside and inside hearing protectors varies by 5-10 dB because communication increases the noise level at the entrance of ear the canal. Currently the best protection for soldiers seems to be active noise cancellation ear muffs that are equipped for communication purposes and worn during the entire military exercise.

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Classical musicians are often exposed to sound levels that exceed the Finnish national action limit value of 85 dB(A). Still, the use of hearing protectors is uncommon among musicians. The purpose of this study was to find out musician's attitudes towards hearing protectors, and under which conditions hearing protectors are used. The study group consisted of five major classical orchestras in the Helsinki region. The players were asked to fill out a questionnaire with questions on hearing protection, ear symptoms, including tinnitus, hearing loss, pain in the ears, and temporary ringing in the ears. Also, questions concerning stress and working environments were asked. Of those who responded, 94% were concerned about their hearing to some degree. Only 6% of the musicians always used hearing protector devices (HPDs). Self-­reported hearing loss was quite common, with 31% of the musicians reporting some hearing loss. Temporary tinnitus was even more common at 37%. There were 15% of women, and 18% of men reporting permanent tinnitus. Hyper-acusis was reported by 43% of the musicians. The ear symptoms affected the usage rate. Hearing protectors were used more often among musicians having ear symptoms (20%) than those reporting no symptoms (6%). Further, the 43% of the musicians found their work to be interesting and meaningful. Stress was experienced to some extent by 60%, and musicians with ear symptoms had three to nine times more stress and felt their working environment noisier. The study shows that musicians seldom use hearing protectors before symptoms begin. Symptoms increased usage rate, but the usage levels are still far from ideal. Motivation and training is needed to improve hearing protector use among musicians.

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European legislation based on the New Approach requires that technical requirements for products are given in harmonised European standards. The Directive 89/686/EEC on Personal Protective Equipment came into force in 1995. The existence of product and testing standards is a prerequisite for the effective implementation of the directive. There was a need to develop several standards in a very short time period and the basic standards for hearing protectors have already been revised once. It is important to continue the validation of the standardized testing methods and requirement levels. This requires good co-operation and research between test laboratories and research institutes, especially as it is necessary to ensure new products comply with these technical requirements.

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Comprehensive protection by use of PPE against the hazards at work requires more than proper selection based on the protection level needed: The PPE user directive (Council Directive 89/656/EEC, Official Journal of the European Communities L 393, 30/12/1989 p. 0018 - 0028) requires an assessment of personal protective equipment itself, which has to consider the risks which may be introduced by use of PPE or use of combinations of PPE. As an example risks which may be introduced by use of hearing protectors are described. Assistance in the assessment required by PPE user directive (Council Directive 89/656/EEC, Official Journal of the European Communities L 393, 30/12/1989 p. 0018 - 0028) and in selection and use of hearing protectors with regard to this assessment is presented.

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From 1953 to 1995 the usage rate of hearing protective devices (HPD) was tracked at a paper mill, a shipyard, and in selected areas of forestry work. For each work period, observations were made of HPD use among workers. In the paper mill, the usage rate increased steadily from 1965. In 1990, 39% of workers used HPDs full-time. At the shipyard, the usage rate remained low up to the mid-1980s, but thereafter the proportion of full-time users rose to 70%. A similar trend was noted in forest workers, with the full-time use at 97% by the 1990s. Due to the increased usage rate in all measured industries, the mean effective noise level at the ear has decreased to below 85 dB.

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European noise research and policy-making ~ overall not so effective thus far ~ is considered from a behavioral science perspective. First, an overview is given of a recent strategy paper by the EU's CALM network ¹ , focused on perception-related and emission-related research. After a summary of noise effects on human well-being, environmental noise problems are discussed as socio-technical problems where the social part is just as important as the technical part. The behavioral and social components of noise emission, transmission, exposure and effect are explicated. Environmental stress is considered as a double-sided phenomenon involving subjects' threat appraisal and their coping appraisal, each comprising specific underlying variables. From the wider perspective explained, several comments are given on the research strategy CALM is proposing. It is argued that: increasing motorization undermines noise abatement; dose-response relationships reflect only part of the problem; more attention is needed for the causative behavior of noisy actors; technical noise-reduction measures are necessary but insufficient; and that noise as a daily stressor should be treated in the context of people's overall quality of life. Specific suggestions are listed for EU noise research and policy-making. One conclusion is that more effective and visionary European noise policies may well be started tomorrow and need not depend on 15 years more research as envisaged in the CALM strategy paper.

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Ear-muffs are commonly used as personal protectors against the effect of noise. The methods of calculation the A-weighted sound pressure level under the cups of ear-muffs are based on the results of laboratory measurements of noise attenuation, which are carried out in the certification process of the product on brand new samples. Hearing protectors are usually stored for certain periods of time. Next, workers use them in different ambient outdoor conditions as long as there are no signs of their physical damage. The question is. What is the influence of ambient outdoor conditions, usage and storage time of ear-muffs on their attenuation? To answer this question, a three-year study has been undertaken. Four types of ear-muffs, most popular in the Polish work environment, made in Europe, meeting the certification requirements and granted a certification mark, were used in this study. Sixty samples of ear-muffs were worn by workers at noisy workplaces, 40 samples were stored and another 40 were exposed to ambient outdoor conditions. The workers were asked to evaluate subjectively the noise attenuation of the ear-muffs. After one, two and three years time of usage and storage, the sound attenuation of ear-muffs was measured. After the two years the headband force and the cushion pressure of tested samples were measured. The results of sound attenuation measurements were used to calculate the attenuation against high- (H), medium- (M) and low- (L) frequency noise and single number rating (SNR) of the tested ear­muffs. The results of the study showed that the attenuation of ear-muffs can be significantly reduced as a function of usage, storage, and exposure to ambient outdoor conditions. The observed decrease of the ear-muffs attenuation corresponded to decrease of the cushion contact area but did not correspond to the subjective workers' assessment.

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The type test of hearing protectors (HPD) for certification purposes will be conducted in laboratory at room temperature. Optionally, the mechanical durability of HPDs will be tested in cold environment by a drop test. The purpose of this study was to find out the relevance of the drop test, the change of performance in HPD protection, and finally to estimate the possible change of protection efficiency against noise in cold environment. In total, 22 HPDs were selected to the measurements: 18 earmuffs, and 4 earmuffs attached to an industrial helmet. Attenuation of each earmuff cup was measured by applying insertion loss method for the test subjects in cold. The change of attenuation and temperature of cushion ring was followed up to nine minutes using 30-second intervals for sampling. Three HPDs were damaged in the test. The replaceable cushion was broken in two earmuffs and in one helmet-mounted HPD. The replaceable parts were replaced, and the HPD with attachment failure was removed from insertion loss measurement. In nine HPDs the relative change was less than 3 dB, and was at worst 10 dB. This change was typically at low frequencies, 125 Hz at the beginning when cooled HPDs were placed. In various HPDs the time to get the attenuation levelled varied from 1.5 minutes to 8 minutes. The recovery was dependent on the temperature of the cushion ring. In all cases the temperature of the full attenuation was achieved when the cushion ring reached 7oC. This temporary decrease in attenuation will have a minor effect to the protection efficiency, when the HPD is used full time during the whole exposure duration. A typical group of forest workers will have their exposure interrupted. The chain saws have to refuel, and the chain needs to be sharpened about every 40 minutes. During 6 hour daily operational time there will be about 9 - 10 minute break, long enough to cool the cushion ring back to below zero at -10oC, if the helmet mounted earmuffs are placed in stand-by position. In the worst case this will cause 1.6 dB increase in daily exposure level to noise.

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