Industrial workers most exposed to job strain

Analysis of the 2003 SUMER survey results reveals five groups of workers who are exposed to risks at work. These risks relate to work-related stress and strain, in line with the ‘Karasek model’. The results indicate that the group of workers most at risk of job strain are those working in industry. Conversely, white-collar workers are the least at risk of job strain among the five groups identified.

Survey methodology

In 2002 and 2003, the SUMER (Surveillance Médicale des Risques [Medical monitoring of risks]) survey was conducted among 1,792 company doctors. The latter survey provides an inventory of employee exposure to the main occupational risks in France. The doctors surveyed completed a questionnaire for 49,984 workers, who were chosen by drawing lots. For half of the panel, a self-completed questionnaire was used, comprised of 26 questions aimed at assessing work-related stress in accordance with the ‘Karasek model’. In the analysis, 20 indicators of work strain were selected, covering the following factors: physical strain, difficult environment, working time and pace of work constraints, rigid organisation, and contact with the public. The responses were processed to identify groups of workers showing homogenous forms of strain.

Identifying the occupational risk groups

The survey identified five main risk groups under the following categories: white-collar workers; ‘hard labourers’; ‘constrained’ workers; those who are ‘under an obligation to the public’; and so-called ‘Zola’ workers who mostly work in industry.

The largest group of workers – white-collar workers – represents some 5.8 million workers; this corresponds to 36% of the working population. The survey found that this group of workers is exposed to a limited number of strains, such as long working days, static position of the neck and head, working at the computer screen for more than 20 hours a week and having frequent interruptions.

The second largest group of workers is composed of so-called ‘hard labourers’; this group is comprised of some 4.2 million workers, representing 27% of the workforce, and mainly consists of men (70%). Workers in this category are exposed mainly to adverse weather conditions and significant physical strain, such as strain in the upper limbs and the manual handling of heavy loads for more than 10 hours a week.

The group referred to as ‘constrained’ workers are primarily exposed to organisational constraints and lack of autonomy, in particular: an inability to interrupt their work, lack of permanent control over the activity, team work, atypical working times. This group is comprised of some 2.7 million workers, totalling 17% of the workforce, the majority of whom are usually employed in large companies with 500 or more workers.

Workers who are ‘under an obligation to the public’ represent some 2.4 million persons – or 15% of the working population – and mostly work in sectors such as education, healthcare, social work and retail trade. People in this category mainly face organisational constraints and situations of tension with the public, which can even lead to physical aggression. Looking at the gender distribution, women represent 55% of the workers in this category.

Highest risk group

The last group of employees, so-called ‘Zola’ workers, are exposed to many different forms of physical strain (harmful noise, painful posture, strain in upper limbs and manual handling of loads for more than 10 hours a week), organisational constraints (teamwork, night work, polyvalence), lack of autonomy and working pace constraints. These workers are not only frequently exposed to job strain, but also face a high risk of social isolation at work, resulting in a lower rate of social support.

Approximately 60% of workers in this category are exposed to more than eight different forms of strain. This group consists of 800,000 workers, representing 5% of the workforce, and largely consists of blue-collar workers from industry, such as car manufacturing, agro-industry or intermediate goods sectors. They are mainly employed in companies with 200 workers or less. Moreover, temporary workers and migrants are overrepresented in this group, comprising three times and 1.5 times the national average respectively.

Evaluation of stress among five groups

An analysis of the self-completed questionnaires enabled an evaluation of the levels of work-related stress faced by these five groups of workers, based on the ‘Karasek model’ (in a simplified form, since ‘work autonomy’ is limited to ‘decision latitude’). The table below presents the main results of these survey findings.

Source: Presentation of the SUMER survey results, 15 March 2006, Paris (unpublished slides)

Reference and further information

Waltisperger, D., ‘Les ouvriers sont stressés eux aussi’ [Workers are also stressed], Santé et Travail, No. 57, Direction de l’Animation de la Recherche, des Études et des Statistiques (DARES), January 2007.

For further information on the findings of the 2003 SUMER survey, see the 2006 EWCO review on working conditions in France.

Anne-Marie Nicot, ANACT