Health and Safety Executive Hand Arm Vibration Calculator

This calculator helps you determine the daily exposure to hand arm vibration using the method established by the Health and Safety Executive (HSE). It calculates the daily exposure action values and provides a risk assessment based on your inputs.

What is Hand Arm Vibration?

Hand arm vibration (HAV) is a type of whole-body vibration that occurs when the hands or arms are exposed to vibration. It is most commonly experienced by workers in industries such as construction, manufacturing, and agriculture who use vibrating tools.

The Health and Safety Executive (HSE) has established guidelines to protect workers from the health risks associated with hand arm vibration. These guidelines include exposure limits and action values to help employers and workers manage the risks effectively.

How to Calculate Daily Exposure

The daily exposure to hand arm vibration is calculated based on the duration and intensity of exposure during a typical working day. The formula used is:

Daily Exposure (m/s²) = √[(Σ (a₁ × t₁)² + (a₂ × t₂)² + ... + (aₙ × tₙ)²) / T]

Where:

aᵢ = acceleration level for each exposure period (m/s²)
tᵢ = duration of each exposure period (hours)
T = total working day duration (hours)

This formula combines the different exposure periods during a working day to provide a single daily exposure value. The result is then compared against the daily exposure action values to assess the risk.

Daily Exposure Action Values

The Health and Safety Executive has established daily exposure action values to help manage the risks associated with hand arm vibration. These values are:

Upper Exposure Action Value (UEAV): 5 m/s²

Lower Exposure Action Value (LEAV): 2.5 m/s²

Exposures above the UEAV indicate a high risk and require immediate action to reduce exposure. Exposures between the LEAV and UEAV indicate a medium risk and may require further assessment. Exposures below the LEAV indicate a low risk and generally do not require intervention.

How to Use This Calculator

To use this calculator, follow these steps:

Enter the acceleration level (in m/s²) for each exposure period during your working day.
Enter the duration (in hours) for each exposure period.
Enter the total working day duration (in hours).
Click the "Calculate" button to compute the daily exposure value.
Review the result and take appropriate action based on the exposure level.

For example, if you have two exposure periods:

First period: 3 m/s² for 4 hours
Second period: 2 m/s² for 2 hours
Total working day: 8 hours

The daily exposure would be calculated as:

Daily Exposure = √[((3 × 4)² + (2 × 2)²) / 8] = √[(144 + 16) / 8] = √[160 / 8] = √20 = 4.47 m/s²

This result indicates a high risk and requires immediate action to reduce exposure.

FAQ

What is the difference between the upper and lower exposure action values?: The upper exposure action value (UEAV) of 5 m/s² indicates a high risk and requires immediate action. The lower exposure action value (LEAV) of 2.5 m/s² indicates a medium risk and may require further assessment.
How often should I use this calculator?: You should use this calculator whenever you have changes in your work activities that may affect your exposure to hand arm vibration. Regular reviews are recommended to ensure ongoing compliance with health and safety guidelines.
What should I do if my daily exposure exceeds the upper action value?: If your daily exposure exceeds the upper action value, you should immediately take steps to reduce your exposure. This may include using less vibrating tools, wearing protective equipment, or adjusting your work practices.
Can this calculator be used for non-work situations?: This calculator is designed for occupational exposure to hand arm vibration. It may not be appropriate for non-work situations where exposure levels are significantly lower.
Where can I find more information about hand arm vibration?: For more information, you can visit the Health and Safety Executive website or consult occupational health and safety guidelines from your local regulatory authority.