Updated HSE HAVS measurement guidance 2024

Does the updated HSE HAVS measurement guidance affect risk assessment?

Yes or No... Which is it?

Yes: if you haven't complied with the previous guidance and have been subject to disingenuous marketing.

No: if you are complying with the standards and the previous HSE guidance.

Unfortunately, many organisations would, usually unwittingly, have to go with Yes. If that is the case, then it can have serious implications re potential HAVS claims and risk management expenditure.

Elements of the HAVS measurement industry publish deliberately disingenuous disinformation. Vibration dosimetry seems plausible and useful. It usually isn't, leading to inflated costs and a false sense that risk reduction has been managed well. The HSE guidance has been specifically written to address this issue.

Q: why are wrist, hand or glove-based monitoring systems deprecated by the HSE?

Q: What does the updated HSE HAVS guidance have to say about what constitutes best practice in HAVS risk measurement?

Read on...

The key elements and implications of the HSE HAVS measurement guidance

Employee exposure monitoring

1: Continuous monitoring of hand-arm vibration exposure is probably not a good use of resources.

• It is costly and you still need to prove that risk is being reduced as far as is practicable. Resources are usually better spent on risk reduction rather than (often placebo) monitoring. There have been substantial fines for organisations that have used continuous monitoring and yet could not demonstrate adequate risk reduction.

2: HSE research shows that the results from continuous monitoring systems vary by up to 20% on the same task. So-called "vibration dosimeters" are just tool timers. They do not measure vibration to the standards. Consequently, you must combine vibration values measured correctly to BS EN ISO 5349 with trigger times to estimate dose for valid comparisons with the Exposure Action and Limit Values.

• Our back-to-back measurements comparing the results of simultaneous vibration measurements on different tool types from hand and wrist-mounted monitors with BS EN ISO 5349 (hard-mounted transducer) data showed that they were inaccurate by between -28% and +240% - and that is assuming they were fitted to the higher vibration hand (they often aren't). The Advertising Standards Authority published a ruling that "... wrist-mounted transducers did not measure hand-arm vibration in accordance with the Standard, did not provide ELV or EAV data that was required by the Regulations and were not, therefore, suitable for risk assessments of hand-arm vibration as set out by the Regulations…"

3: Initial exposure time monitoring (combined with accurate tool vibration data) can be used to rank risk and limit the exposure of employees assessed as high risk. You might also periodically sample exposure times if you feel that the work has changed and to verify that control measures are effective. You should not need to monitor daily vibration exposures.

• Trigger times can be measured by hand or via low-cost electronic or pneumatic timers. We often recommend buying a few devices and then moving them from tool to tool to acquire statistically valid finger-on-trigger time data.

Workplace vibration measurements

1: Only measure vibration if you can't acquire valid field tool use data from reputable sources.

• Most of our HAVS risk evaluations are largely based on virtual assessments (as recommended by the HSE) using field data from our HAVBase online database. This saves time and money (accurate measurement is time-consuming and costly). The saved resources are better spent on risk reduction.

2: If you have to measure vibration, make sure the person is competent. Accurate vibration measurement is time-consuming and many variables must be taken into account to ensure the results are representative of the activity tool use. Measurement results are unlikely to be representative if you measure away from the palm of the hand or use a measurement position that is on the fingers, back of the hand or wrist

• Running the IOSH HAVS competency courses, we far too often see the results of incompetent measurements, from transducers held on with tape to hand-held transducers to meter overloads (no filter used) to incorrect transducer locations. It is important to understand that the objective is to acquire vibration data to the BS EN ISO 5349 standard that is representative of the tool use on particular activities/workpieces. This takes care, considerable organisation, and multiple measurements of the same tool. The result will be a representative range of values that can be combined with trigger times to estimate and rank vibration doses. We add data from HAVBase to generate better statistical ranges of values to improve the dose calculation accuracy.