How to Prevent Risks Linked to Mechanical Vibrations?

Discover the regulatory obligations regarding the prevention of risks linked to mechanical vibrations

Clara Godin
Juriste en droit de l'environnement & santé-sécurité au travail
Publication : 
15.11.2023
Table of Contents
Example H2
Request a demo

Please note: This article concerns French legislation. The requirements described may not apply in other countries.

‍

Construction work, metalworking... exposure to mechanical vibrations is a reality for many workers. As such, specific prevention measures must be put in place to protect the health and safety of the employees exposed to them.

What is a mechanical vibration?

What is the definition of a mechanical vibration?

A mechanical vibration is transmitted through the operation and use of a work tool. Depending on the work equipment used, these vibrations can reach thresholds that pose a danger to workers' occupational health and safety (OHS).

The Labour Code distinguishes between two types of vibration (Article R4441-1 of the Labour Code):

  • vibrations transmitted to the hands and arms, which can cause risks of vascular disorders, osteoarticular injuries, or neurological or muscular disorders;
  • whole-body vibrations, which can lead to risks of lower back pain and spinal microtrauma.

Exposure to mechanical vibrations is present in many sectors of activity (mainly construction, mechanical engineering and metalworking) and thus raises a genuine occupational health and safety issue.

Examples: lumberjacks using a chainsaw, construction workers using a jackhammer or piece of site equipment, workers in industrial sectors using tools, or simply working near a piece of work equipment that emits strong vibrations.

What are the exposure thresholds for mechanical vibrations?

Exposure to mechanical vibrations can be more or less significant depending on the duration of exposure and the work tool usedThe Labour Code sets regulatory thresholds to govern situations exposing workers to significant and/or prolonged vibrations.

These exposure thresholds are calculated over an eight-hour working day (Article R4441-2 of the Labour Code). These are known as daily exposure limit values (ELVs).

This mechanical vibration exposure limit value is (Article R4443-1 of the Labour Code):

  • 5 m/s2 for vibrations transmitted to the hands and arms;
  • 1.15 m/s2 for whole-body vibrations.

Any situation or workstation exceeding these thresholds is prohibited and represents a genuine danger to workers.

📃 Documentation: you can find the calculation method for daily exposure to mechanical vibrations on the dedicated page of the French National Research and Safety Institute (INRS) website.

Furthermore, specific prevention measures must be triggered when the mechanical vibration exposure value exceeds (Article R4443-2 of the Labour Code):

  • 2.5 m/s2 for vibrations transmitted to the hands and arms;
  • 0.5 m/s2 for whole-body vibrations.

These values are also known as action values (AVs).

⚠️ Please note: it is prohibited to assign young workers to work exposing them to a vibration level above the action values (Article D4153-20 of the Labour Code).

What are the regulatory obligations regarding the prevention of risks linked to mechanical vibrations?

Preventing risks of exposure to mechanical vibrations is based on the general principles of prevention (Article R4442-2 of the Labour Code). The employer must therefore take measures to eliminate or minimise exposure to mechanical vibrations (Article R4442-1 of the Labour Code).

Given the specific risks arising from exposure to mechanical vibrations, the occupational risk assessment must follow a precise procedure that takes into account, at a minimum (Article R4444-5 of the Labour Code):

  • the level, type and duration of exposure, including exposure to intermittent vibrations or repeated shocks;
  • the daily exposure limit value (ELV) thresholds and the action value (AV) thresholds;
  • the profiles of exposed workers, in particular pregnant women and young workers under 18;
  • the impact of vibrations on safety and on carrying out the work;
  • information on vibrations provided by manufacturers of the work equipment;
  • the use of work equipment that helps reduce mechanical vibrations;
  • cumulative risk factors in the case of specific working conditions (such as low temperatures);
  • the opinions of the occupational health and prevention service.

🔎 Focus: with the help of the occupational physician, the employer must adapt prevention measures to workers' needs in relation to the risks arising from exposure to vibrations (Article R4445-5 of the Labour Code)

As a reminder, the assessment of risks from exposure to mechanical vibrations must be recorded in the single occupational risk assessment document (Article L4121-3-1 of the Labour Code).

If the risk assessment reveals that certain workers are exposed to vibrations, the employer must measure the levels of exposure to mechanical vibrations. These measurements determine whether the regulatory thresholds are exceeded (Article R4444-1 of the Labour Code).

These measurements must be carried out by competent persons, with the assistance of the occupational health and prevention service if necessary (Article R4444-2 of the Labour Code). Furthermore, the results must be kept for 10 years and made available to the Social and Economic Committee (CSE), the occupational physician, and the labour inspectorate (Article R4444-3 of the Labour Code and Article R4444-4 of the Labour Code).

⚠️ Please note: the labour inspectorate can require the employer to have mechanical vibration exposure measurements carried out by an accredited body (Article R4722-18 of the Labour Code).

Note that since 1 October 2017, the professional prevention account (C2P) no longer takes into account the occupational risk factor linked to mechanical vibrations. Employees can therefore no longer accumulate points for this exposure.

However, this occupational risk factor is taken into account in the following two cases:

  • for an employee recognised as having an occupational illness and suffering from a permanent incapacity of at least 10%: entitlement to early retirement;
  • for an employee recognised as having an occupational illness without reaching a permanent incapacity of 10%: with the employer's agreement, the possibility of moving to part-time work, up to a limit of 50%, for the 2 years before retirement.

How can exposure to mechanical vibrations be reduced?

Prevention actions

When the regulatory threshold is exceeded, the employer must implement an action plan to reduce mechanical vibrations, in particular using the following measures (Article R4445-2 of the Labour Code):

●     using work methods that reduce or limit the duration and intensity of exposure to mechanical vibrations;

●     using appropriate work equipment that produces as little vibration as possible;

●     using equipment that effectively dampens transmitted vibrations;

●     maintaining work equipment and the workplace;

●     modifying and laying out work areas and workstations;

●     providing workers with adequate information and training;

●     limiting the duration and intensity of exposure;

●     organising working hours and rest periods.

🔎 Focus: The protective equipment used must be effective enough to reduce vibrations below the thresholds (Article R4445-3 of the Labour Code).

Training

Training is an effective way to prevent occupational risks. Proper use of work equipment helps limit the risks of improper handling and ensures optimal performance.

Workers exposed to vibration risks must therefore be trained and informed on (Article R4447-1 of the Labour Code):

  • the techniques and professional practices that minimise the risks arising from exposure to mechanical vibrations;
  • the measures put in place to eliminate or minimise mechanical vibrations;
  • the vibration thresholds to which they are exposed;
  • the regulations on maximum exposure to vibrations;
  • the illnesses and injuries caused by the use of work equipment that produces vibrations, as well as their symptoms;
  • the individual health monitoring they receive.

Medical monitoring

Workers exposed to mechanical vibrations benefit from medical monitoring, which includes an initial information and prevention visit (VIP) carried out by a healthcare professional, and a periodic visit based on the worker's working conditions, state of health, age, and the occupational risks to which they are exposed.

⚠️ Please note: the VIP must take place within three months of the worker starting their position (Article L4624-1 of the Labour Code).

The VIP serves a dual purpose: on the one hand, it allows the worker to be informed of the risks they are exposed to as part of their work, and on the other hand, it allows the worker's fitness to carry out their role to be checked in light of these risks.

The worker can also request a medical visit if they feel the need due to their state of health and working conditions.

Through monitoring workers' state of health, the occupational physician analyses and monitors the risks to which employees are exposed. This is why the occupational physician must inform the employer if they identify a deterioration in workers' state of health.

The employer must then draw the necessary conclusions from the occupational physician's opinion and may in particular need to review the risk assessment and the prevention measures put in place (Article R4446-3 of the Labour Code).

Conclusion

Exposure to mechanical vibrations is an occupational risk factor that requires specific prevention measures. Depending on the degree of employee exposure, additional prevention actions must be put in place. Beyond risk prevention, mechanical vibrations can cause genuine discomfort, and eliminating or reducing them also has a positive effect on employee wellbeing.