Hand-Arm Vibration Update
The HSE's released a revised Hand-Arm Vibration (HAV) exposure calculator in September 2019. This calculator helps estimate and record workers' exposures to HAV and compare them with the action values in the regulations as part of a HAV risk assessment. You can access the revised calculator by clicking here. The calculator also has a help/instruction tab to help guide you through the process, although this is covered later in the bulletin.
The calculator includes a drop down for vibration magnitudes for common tools from the HSE's HAV database. It can be used to make cautious estimates of exposure before representative in-use data for specific tools is available.
Guide to using the HSE HAV exposure calculator
1. The calculator is a Microsoft Excel file which may be downloaded and saved on your computer.
2. Click on the white areas and enter a representative vibration magnitude (in m/s²) and an exposure duration (in hours and/or minutes). You can do this for up to six different machines or processes. Information on tool types may be entered directly into the tools/process names columns, or selected from a drop-down list of common tools with HSE's recommended initial value.
3. When you have entered all the numbers, press the ENTER key, or click on a different cell. The following values will then be calculated and displayed in the yellow cells on the right:
a. Partial exposure (shown in both m/s² A(8) and exposure points) for each tool or process, as calculated from the vibration magnitude and the exposure duration.
b. Daily exposure, also in m/s² A(8) and exposure points, as calculated from the partial exposures.
4. In addition to the partial and total exposure values, the calculator also uses the vibration magnitudes to produce the following values:
a. Exposure points per hour. The number of exposure points for every hour of exposure time for the individual machine or process.
b. Time to reach EAV (exposure action value). This is the total exposure time required for the individual machine or process, before the EAV (2.5 m/s² A(8) or 100 points) is reached.
c. Time to reach ELV (exposure limit value). This is the total exposure time required for the individual machine or process, before the ELV (5 m/s² A(8) or 400 points) is reached.
5. The illustration below shows the calculator in use. In this example, an operator uses three machines during a working day. The vibration magnitudes are 10, 6 and 3.5 m/s² and the total exposure times are 15, 30 and 90 minutes respectively. For the first tool (a 1" impact wrench), the tool has been selected from the drop-down list, this automatically enters a vibration value of 10 m/s², which is the "recommended initial value" for that tool from the HSE table. For the other tools the values have been typed into the white cells. When entering exposure duration information, you can use hours, minutes or a combination of the two. The results (in the yellow cells) show the partial exposure values for the three machines and the total exposure which is 2.8 m/s² A(8) or 123 points. Since the result is above the exposure action value a warning is displayed below the daily vibration exposure values.
6. The cells can be cleared for another calculation by clicking on the Reset Options in the bottom left-hand corner.
Note: When you open the spreadsheet you may see a Microsoft Excel message asking you to decide whether to enable or disable macros. If your system settings allow it, you should enable macros. If not, the Reset button will not work. However, the white cells can still be cleared by deleting the contents manually.
Hand-Arm Vibration L140 - Second Edition
Hand-arm vibration is a widespread hazard for employees in many industries and occupations. The second edition of L140 outlines what an employer's duties are under the Control of Vibration at Work Regulations 2005 as they relate specifically to HAV. It covers the management and control of the risks from HAV and how to protect employees, with practical guidance on risk assessments, controlling vibration exposure and arranging health surveillance.
The guidance book looks at the employer's legal obligations to control risks to employees' health and safety, from exposure to HAV and to prevent HAV-related diseases such as hand-arm vibration syndrome (HAVS) and carpal tunnel syndrome (CTS). HAVS and vibration induced CTS together, account for two thirds of the ill-health cases reported through RIDDOR.
The L140 guidance document is attached with this Bulletin, for your reference.
Should you require any further information, clarification or assistance with HAV, please contact us on firstname.lastname@example.org or 01268 649006