Vibrations

• 16.04.2015
• 17:00

Working with vibrating machines or equipment may cause health damage. Training in correct use of work equipment, together with information about measures which can reduce the effects of the vibrations, may be essential to avoid injuries

Mechanical vibrations refer to vibrations transmitted from work equipment to hand and arm, which may cause vascular, bone, joint, neurological or muscular disorders, and which may also pose a safety risk.

Whole-body vibrations are mechanical vibrations transmitted to the whole body entailing risk of health damage, especially to the spine, and which may also pose a safety risk.

The vibrating object may for instance be the handle of a drill or a steering wheel. Most vibrations are composed of motions in different directions, frequencies and size of oscillations. Usually, vibrations are measured in m/s², which describes the acceleration of the movement.

There are different exposure limits and action values for vibration stated in Regulation concerning the working environment, health and safety of workers on board ship (link to NMA website).

Hand-arm vibrations entail risks of damage to blood vessels, nerves, muscles and joints. Symptoms may be “white fingers” (Raynaud’s phenomenon), pain, reduced strength and difficulties in coordinating movement.  If a worker on board is exposed to vibrations exceeding the exposure action values in § 14-5, and which pose a risk to the health of the worker on board, he or she should be given the option of an appropriate medical examination. A relocation of workers due to health-related reasons may prove necessary. Vibrations may also pose a safety risk.

Circumstances that might reduce hand and arm vibrations

• Use of low vibration equipment – normally has greater effect than reduced exposure time
• Reduce exposure time
• Alternative work methods and/or tools
• Improve work techniques, for instance by avoiding use of more energy than necessary
• Anti-vibration gloves

Circumstances that might increase hand and arm vibrations

• Lack of maintenance on work equipment
• Insufficient knowledge, for instance when equipment is purchased
• Exposure time (how long one is exposed)
• Joints in unfortunate positions
• Use of energy (the weight of the tool or the energy used for carrying out a task)
• Cold and humidity
• Smoking (nicotine)
• Medication (for instance some blood pressure reducing medication) and certain illnesses

Training and information

The worker on board and the safety representative shall receive information and training in accordance with results of risk assessments carried out prior to work tasks.

Information and training shall be given in regard to:

• preventive measures to remove the risk of mechanical vibration or to reduce the risk to a minimum
• limit values and action values
• the result of the assessments and measures carried out and the potential injury arising from the work equipment in use
• why and how to detect and report signs of injury
• the circumstances in which workers are entitled to health surveillance
• safe working practices to minimize exposure to mechanical vibrations.

Relevant literature:

Ergonomics - noise - vibrations (pdf)