Vibration (ALL)

Question 1

The international standard for human vibration measurement

Answer 1

Acceleration is measured in metres per second per second (m/s2).

Question 2

Whole-body vibration is

Answer 2

shaking or jolting of the human body through a supporting surface (usually a seat or the floor), for example: when driving or riding on a vehicle along an unmade road, operating earthmoving machines or standing on a structure attached to a large, powerful, fixed machine which is impacting or vibrating.

Question 3

Hand arm vibration is

Answer 3

vibration transmitted from work processes into workers’ hands and arms. It can be caused by operating handheld power tools, such as road breakers, and hand guided equipment, such as powered lawnmowers, or by holding work pieces being machined.

Question 4

A tiered approach to health surveillance is sensible.

Answer 4

 The first level is to use questionnaires to identify workers who may be at risk or may be experiencing early symptoms.  The second level would involve an assessment by an occupational health nurse. If ill-health was indicated the third level would involve a referral to an occupational health physician for a formal diagnosis.  Medical assessments are more appropriate for hand arm vibration syndrome (HAVS) as the early signs of vibration white finger (VWF) can be tested for.

Question 5

The HSE has also developed a simple ‘exposure points’ system to estimate the daily exposure –

Answer 5

Multiply the points assigned to the tool vibration by the number of hours of daily ‘trigger time’ for the tool(s) and then compare the total with the exposure action value (EAV) and exposure limit value (ELV) points. EAV = 100 points per day ELV = 400 points per day

Question 6

Hand Arm Vibration (HAV) What are the risk factors?

Answer 6

 Frequency of the vibration - 2 to 1,500 Hz is potentially damaging - 5 to 20 Hz is most dangerous  Magnitude of the energy measured in m/s2  Strength of the grip and other forces necessary to hold or guide the tool or work-piece  Duration of exposure  Frequency of exposure  Low temperature  Individual factors, for example: smoking, susceptibility to vibration energy, age, health and general well-being

Question 7

Hand Arm Vibration (HAV) Exposure Action Value (EAV)

Answer 7

 Above which employers are required to take action to control exposure  2.5 m/s2 A(8)

Question 8

Hand Arm Vibration (HAV) Exposure Limit Value (ELV)

Answer 8

 Maximum amount of vibration an employee may be exposed to on any single day  5 m/s2 A(8)

Question 9

Hand Arm Vibration (HAV) How is it controlled?

Answer 9

 Eliminate the need for a worker to hold vibrating equipment, for example: automate a process  Minimise the required force or grip on the tool or work piece  Provide suitable low vibration tools  Ensure the right tool is used for each job  Ensure tools have been properly maintained to avoid increased vibration caused by faults or general wear, and keep cutting tools sharp so that they remain efficient  Reduce the amount of time vibrating tools are used (work scheduling / job rotation / rest breaks)  Use of dose monitors / limiters  Keep workers warm and dry (provide gloves, a hat, waterproofs and heating pads if required)  Provide workers with information and training on the risks and precautions

Question 10

Whole Body Vibration (WBV) What are the risk factors?

Answer 10

Unusually high vibration or jolting or the vibration is uncomfortable for a long time on most working days

Question 11

Whole Body Vibration (WBV) Exposure Action Value (EAV)

Answer 11

 Above which employers are required to take action to control exposure  0.5 m/s2 A(8)

Question 12

Whole Body Vibration (WBV)Exposure Limit Value (ELV)

Answer 12

 Maximum amount of vibration an employee may be exposed to on any single day  1.15 m/s2 A(8)

Question 13

Whole Body Vibration (WBV) How is it controlled?

Answer 13

 Select vehicles and machines with the appropriate size, power and capacity for the work and the ground conditions.  Maintain vehicle suspension systems correctly (for example: cab, tyre pressures, seat suspension).  Make sure that paved surfaces or site roadways are well maintained, for example: potholes filled in, ridges levelled, rubble removed.  Train and instruct operators and drivers to be able to adjust seat positioning and driver weight setting on suspension seats.

Question 14

The risk assessment should consider:

Answer 14

(a) the magnitude, type and duration of exposure, including any exposure to intermittent vibration or repeated shocks (b) the effects of exposure to vibration on employees whose health is at particular risk from such exposure (c) any effects of vibration on the workplace and work equipment (d) manufacturers information (e) the availability of lower vibration replacement equipment (f) any extension of exposure beyond normal working hours including at rest facilities (g) specific working conditions such as low temperatures (h) appropriate information obtained from health surveillance