Understand exposure.Act with confidence.

Repeated shock and whole-body vibration are related, but they are not interchangeable. Impact monitoring records individual shocks. WBV assessment considers the frequency-weighted vibration reaching a person and the time over which it accumulates.

A journey with few severe impacts can still create meaningful exposure across a working day. Good awareness starts with recognising both forms of risk and understanding what the evidence is showing.

• Individual shock events
• Frequency-weighted vibration
• Exposure duration
• Journey and operating context

Crew members influence exposure through the way they prepare, sit, brace, communicate and respond as conditions change. Everyone on board should understand the expected conditions, the equipment provided and the actions to take when the ride becomes demanding.

Concerns should be reported early. A severe impact, persistent discomfort, numbness, unusual fatigue or difficulty maintaining a safe posture all deserve attention rather than becoming accepted as part of the job.

• Take part in the pre-departure briefing
• Use seats, foot supports and handholds correctly
• Respond to operational guidance
• Report impacts, discomfort and concerns

Managers need a credible process for recognising changing conditions, evaluating exposure and acting on the evidence. That includes competent risk assessment, suitable information and training, maintained equipment, clear reporting routes and a review of whether controls actually worked.

The most effective response depends on the operation. Controls may include changing speed or course, selecting a different route or time, reviewing seating and maintenance, or changing work and recovery patterns.

• Plan for route and sea conditions
• Review seating, equipment and maintenance
• Manage task duration and recovery
• Record actions and confirm their effect

VIMMS gives the crew real-time feedback while there is still an opportunity to alter the operation. It also retains WBV, impacts, speed, position and journey context so managers can investigate the cause of exposure after the vessel returns.

The objective is not simply to collect a number. It is to identify when exposure is increasing, relate it to the real operation and make a proportionate change that can be reviewed later.

• Real-time helm feedback
• Person-linked WBV history
• Impact and journey context
• Evidence for follow-up and review

For whole-body vibration, the eight-hour daily exposure action value is 0.5 m/s² A(8), while the exposure limit value is 1.15 m/s² A(8). Reaching the action value means exposure must be reduced so far as is reasonably practicable. The limit value must not be exceeded.

These values support decisions; they do not replace judgement. Exposure should be considered alongside the route, sea state, speed, seating, task, work pattern and person involved.

• Below the action value: record and review
• At the action value: introduce controls
• At the limit value: take immediate action
• After action: reassess and confirm

This page is a basic awareness resource. It is not a certificate, a competent risk assessment or a substitute for practical training suited to the vessel, role and operation.

NextGen Marine delivers a four-hour Marine Repeated Shock and Whole-Body Vibration Awareness course for managers, crews and professional passengers. Training can be arranged for an organisation or joined as part of a mixed group, in person or online.

• Crew and manager awareness
• Repeated shock and WBV
• Practical risk-reduction measures
• Certificate supporting CPD