HAVS surveillance
Hand Arm Vibration Syndrome (HAVS) can cause painful vascular (circulatory) or sensori-neural (tingling and numbness) problems with the fingers and hands. There is a strong dose-response relationship between the vibration exposure (trigger time and vibration magnitude) and the extent of the symptoms. The greater the exposure the more severe the symptoms.
HAVS health surveillance is required when:
- Exposure is over the first action level (2.5m/s2), or lower if the individual is vulnerable due to existing health problems such as poor circulation, Raynauld’s Phenomenon.
- There is already a diagnosis of HAVS
Levels 1 and 2 take around 15 minutes to complete and can be done either remotely or together with the individual.
Level 3 takes between 60 and 90 minutes depending on the symptoms of the individual and the difficulties they are experiencing.
Levels 4 and 5 will depend on the results of level 3.
There are 5 levels of HAVS health surveillance assessment identified in the Control of Vibration at Work Regulations:
Level 1 – this is a questionnaire which should be issued to new starters who are likely to be exposed to HAVS and used to check previous exposure and symptom history.
If problems are identified on this questionnaire, they should be referred to an Occupational Health Nurse or doctor who is specially qualified in HAVS screening for a level 3 or 4 HAVS screening. Individuals should be cleared fit to work with vibration.
Level 2 – this is an annual questionnaire which should be issued to all employees exposed to vibration levels over the first action level. It is required annually.
If problems are identified on this questionnaire, they should be referred to an Occupational Health Nurse or doctor who is specially qualified in HAVS screening for a level 3 or 4 HAVS screening.
Level 3 –this is a screening assessment undertaken every three years which should be carried out for all employees exposed to vibration levels over the first action level. It involves a questionnaire and lots of tests to check for circulatory, neurological and musculo-skeletal problems. It is also used to investigate problems at levels 1 or 2 and for monitoring those who have been diagnosed with HAVS to ensure it is stable.
Level 4 – this is carried out when someone has been identified with symptoms consistent with HAVS at level 3 assessment and a diagnosis by a doctor is required. It may also be required to monitor newly diagnosed employees to ensure that their symptoms remain stable. If a diagnosis is made, the incident must be reported under RIDDOR. It builds on from the level 3 medical to include formal clinical examination and diagnosis.
Level 5 – this assessment is undertaken at Specialist Centres located regionally and is used to confirm diagnosis where the case is complex or where clarity is required for legal purposes. It is not used routinely.
If abnormalities are detected, they will need to be investigated appropriately. Risk assessments and safe exposure levels should be reviewed accordingly..
If the HAVS staging is unclear, the following actions should be taken:
- the individual should be referred for a level 4 or level 5 HAVS screening,
- duties should be restricted according to the Occupational Physician’s guidance;
- once a diagnosis has been confirmed, the case should be reported as a work-related health problem in the employer’s accident book and under RIDDOR;
- surveillance should be continued at levels 3 or 4 on regular basis identified by the doctor making the diagnosis.
In addition to Hand Arm Vibration Syndrome, Carpel Tunnel Syndrome is another health hazard associated with vibration. It is important to consider the ergonomics of work involving vibration to reduce the risks from Carpel Tunnel Syndrome as well as HAVS.
How often should HAVS be undertaken?
Level 1 HAVS surveillance should be conducted at the new-starter stage.
Level 2 HAVS surveillance should be conducted annually for those who do not have any symptoms of Hand Arm Vibration Syndrome (HAVS) with a level 3 surveillance being conducted every 3 years.
Level 3 HAVS surveillance should be conducted annually for anyone with symptoms or diagnosis of HAVS. This should be undertaken whether the individual continues to be exposed to vibration or not.
Level 4 and 5 HAVS surveillances should be conducted at the request of the Occupational Health professional conducting the level 3 surveillance.