Hi All,
I'm confused about EAV and ELV, if a hand held power tool has an EAV time to reach EAV: 1h 23min and ELV of 5h 30min, what does that mean? Should the operator only use the tool for a max of 5h 30 min or 1h23 min? (according to the HSE calculator).
The tool in question has a vibration of 6m/s2
I'm struggling to understand why theres 2 values and how they cross over or link?
Thanks, (first post by the way)
Vibration Exposure Limits
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Re: Vibration Exposure Limits
Hi Timo
Welcome to the site.
The 2 values can be explained from this on HSE site:
The exposure action value (EAV) is a daily amount of vibration exposure above which employers are required to take action to control exposure. The greater the exposure level, the greater the risk and the more action employers will need to take to reduce the risk. For hand-arm vibration the EAV is a daily exposure of 2.5 m/s2 A(8).
There is also a level of vibration exposure that must not be exceeded. This is called the exposure limit value.
The exposure limit value (ELV) is the maximum amount of vibration an employee may be exposed to on any single day. For hand-arm vibration the ELV is a daily exposure of 5 m/s2 A(8). It represents a high risk above which employees should not be exposed.
So if an employee is using a tool then the EAV gives the employer a limit (2.5 m/s2) they must try and reduce their exposure to keep it as low as reasonably practical to do so (ALARP). The ELV is the max any person should ever be exposed to on a single day. Any more than that limit a employee should never be exposed to.
So for example with your tool of 6m/s2
To reach the EAV (2.5 m/s2) a employee can have trigger time of 1hr 23 min so they should not be exposed to any more vibration than that without controls in place. To reach the ELV they could use the trigger time of 5 hrs 33 min
If the task trigger time using that kit was 1 hours trigger time they would achieve a daily exposure of 2.1 m./s2 (so below the EAV) if they used it for 3 hours trigger time it would give them a daily exposure of 3.7m/s2 so above the EAV.
Good training would explain it more than I can, INVC offer excellent training though there are plenty of other good companies who could help you more
Penfold
Welcome to the site.
The 2 values can be explained from this on HSE site:
The exposure action value (EAV) is a daily amount of vibration exposure above which employers are required to take action to control exposure. The greater the exposure level, the greater the risk and the more action employers will need to take to reduce the risk. For hand-arm vibration the EAV is a daily exposure of 2.5 m/s2 A(8).
There is also a level of vibration exposure that must not be exceeded. This is called the exposure limit value.
The exposure limit value (ELV) is the maximum amount of vibration an employee may be exposed to on any single day. For hand-arm vibration the ELV is a daily exposure of 5 m/s2 A(8). It represents a high risk above which employees should not be exposed.
So if an employee is using a tool then the EAV gives the employer a limit (2.5 m/s2) they must try and reduce their exposure to keep it as low as reasonably practical to do so (ALARP). The ELV is the max any person should ever be exposed to on a single day. Any more than that limit a employee should never be exposed to.
So for example with your tool of 6m/s2
To reach the EAV (2.5 m/s2) a employee can have trigger time of 1hr 23 min so they should not be exposed to any more vibration than that without controls in place. To reach the ELV they could use the trigger time of 5 hrs 33 min
If the task trigger time using that kit was 1 hours trigger time they would achieve a daily exposure of 2.1 m./s2 (so below the EAV) if they used it for 3 hours trigger time it would give them a daily exposure of 3.7m/s2 so above the EAV.
Good training would explain it more than I can, INVC offer excellent training though there are plenty of other good companies who could help you more
Penfold
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Re: Vibration Exposure Limits
Good advise from Penfold above!
Think of the values like the Noise values of 80dBA and 85dBA. You have to do something over the first value as hearing might be damaged but you must do something over 85dBA as hearing will be damaged.
We always tried to keep below the EAV.
The workers would record their trigger times and we would assess if they were keeping below the EAV and take action if they were not.
For example, standard working practice was 2 days of welding followed by 2 days of grinding creating huge spike in vibration exposure. We changed the working practices so it was more evenly balanced across all days.
We had handheld tools that were as high as 12m/s2.
If they used a combination of tools the EAV could be as low as 20 minutes per day!
Think of the values like the Noise values of 80dBA and 85dBA. You have to do something over the first value as hearing might be damaged but you must do something over 85dBA as hearing will be damaged.
We always tried to keep below the EAV.
The workers would record their trigger times and we would assess if they were keeping below the EAV and take action if they were not.
For example, standard working practice was 2 days of welding followed by 2 days of grinding creating huge spike in vibration exposure. We changed the working practices so it was more evenly balanced across all days.
We had handheld tools that were as high as 12m/s2.
If they used a combination of tools the EAV could be as low as 20 minutes per day!
'Train people well enough so they can leave, treat them well enough that they don't want to!' - Richard Branson
Re: Vibration Exposure Limits
Thanks, that explains things a lot better, I understand how it all works now. Im having a proper servery carried out next week to determine actual trigger time and vibration levels.