[The role of ergonomics in the prevention of work-related diseases].

Processes linking individual situations and behaviours, as disclosed by the ergonomic analysis of job, to populations' epidemiological characteristics are discussed here. Epidemiology proposes deterministic models of general significance, reflecting stable phenomenons within wide populations. Ergonomics proposes cybernetic (or systemic) models of time- and space-limited significance, reflecting the variety of adapting and assimilating behaviours in homogeneous groups of workers.

[The role of ergonomic analysis of work in the detection, evaluation and prevention of chemical risk].

In this paper, observations are presented to show the role played by the ergonomic analysis of working procedures, when detecting, measuring and preventing chemical hazards. At first, unsuspected hazards can be detected, when watching real operative practices. Secondly, the knowledge of each activity may question the validity of general standards.

[Divergent opinions concerning the perception of chemical risk].

In Switzerland, employers and employees are requested to settle together the amount of risk and priorities for each industrial activity, for the needs of a federal commission in charge of occupational health specialists. After our results, this aim will be difficult to achieve, since the feelings of employers and employees on similar safety problems vary widely. In particular, chemical risks did not evoke similar reactions in employers and employees of the French and of the German-speaking regions.

[Perception of noise and work load].

An ergonomic research performed in 16 plants of various activities shows that 47.2% of the workers are complaining on noise. We prove that the annoyance is not only related to the exposure level in db(A), but also to task performance and essentially mental load.

[Night work: a choice of society?].

The methodology and first results of a research on night-work management, carried out by the PNR 15, are presented. We show that the effects of night-work and the way it is experienced by the workers, varies from one person to another, and mainly depend on the type of activity concerned and on work conditions. With the aim of prevention, we try to define risk-populations.

[Occupational medicine in Switzerland: wishes and reality].

Some results on occupational health are presented, based on a questionnaire named "Integration of occupational health in the Swiss sanitary system", which was mailed to every industrial societies employing more than 100 persons and unions in Switzerland. The results show differences between societies and unions as well as between the two main linguistic areas and that the largest societies are more in favour of the expansion of occupational health than the smallest.

[Is it dangerous to patronize discotheques?].

Sound levels measured during 6 music-exhibitions are situated, for the equivalent level (Leq), between 92 and 105 dB(A), and peaks of 120 dB(A) have been measured. Audiograms recorded before and after the exhibitions show a great auditive fatigue. Musicians and usual spectators present in comparison with nonexposed subjects of the same age a lightly impaired sensibility of hearing.

[Alveolysis in adolescents: prevalence and correlation with the DMF index, the OHI-S index and the PM index according to sex, age and occupation (Geneva 1970-1972)].

A randomized sample of 1392 girls and boys, 16 to 20 years old and living in the canton of Geneva have been studied through their own history, clinically and radiologically in 1970-72 during an epidemiological and socio-economical study. The rate of alveolar bone resorption (radiographic method of Marshall-Day and Shourie, with Schei grid), the degree of gingival inflammation (PM index), the oral health (OHI-S index) and the carious frequency (DMFS index) have been determined. For the same sample, an indication of the duration of caries prevention through fluoride tablets, the frequency of daily toothbrushing and the dento-facial anomalies (Angle classes) were known.

[Demonstration of a control lever for a simulator of visual aptitudes].

In this paper, the design and testing of the control of a new visual screener are described. The equipment is composed of a push-pull lever, an electronic digitalizer and a display on which Landolt rings are presented. The problem to be solved was to check whether the eight directions in which the lever could be oriented were equally reliable.

[Level of SO2 pollution and the prevalence of bronchitis].

The prevalence of chronic bronchitis (according to the BMRC questionnaire on respiratory symptoms) for 1182 male smokers, as well as their peak flow rate, are related to age (18-65 years), cagarette consumption (1-55 cig./day) and exposure to atmospheric SO2 pollution (20-65 microgram/m3).

[Discrimination and classification based on characteristics of bucco-dental data].

Discriminant analysis and its corresponding classification procedures are illustrated by means of two practical applications pertaining to a dental health survey. The discriminating variables refer to dental caries, oral hygiene, periodontal diseases and fracture of anterior teeth. Their relative discriminating power is discussed.

[Functional bucco-dental restoration cost for adolescents aged 16 to 20 in the Geneva resident population (survey 1970-72). I. -- Description of estimates (author's transl)].

In 1970/72, a random sample of 1392 adolescents of the population irrespective of nationality and sex has been drawn, using computer equipment, from the Geneva (Switzerland) resident population, ages 16 to 20 years. The sampling fraction was 13%. These adolescents were interviewed for case history, and then underwent clinical, radiological and photographic examination by a medically trained team including a dentist and a dental hygienist.

[A method of visual representation for the distribution of variables in the Geneva area].

Using a 10,000 square meter partition of the Geneva area, a computer mapping was developped for the geographical distribution of variables such as population density or pollutants emissions. An example is given in which the method is applied to epidemiological date (age and respiratory performance of a population sample).

[Alveolar CO as an index of ambiant CO in schoolchildren (author's transl)].

As it is impossible to use alveolar CO as an useful index of the exposure to ambiant CO in smokers, young children between 8 and 11 were used in this study, who had no contact with smoking. In a sample of 306 schoolchildren living in rural or urban areas, it was shown: a) that the technique which is usually employed in adults to get a sample of alvelolar air was applicable to young children, b) that alveolar CO concentrations did reflect very closely in these children ambiant CO concentrations, c) that smoking habits of parents have to be taken into account before assessing the relationship between alveolar CO concentrations and exposure.

[Computer estimates of the cost for restorative dental treat].

The costs for a complet functional restoration of the dentition and the parodontium (orthodontics not included) in a sample of 1392 adolescents aged 16-20 (Geneva, 1970-1972) have been estimated on the basis of an approved scale of fees (1). These costs are analyzed with respect to age, sex, occupation and socio-professional status of the parents.