Introduction to Health and Safety at Work

Whole-body vibration (WBV)
Whole-body vibration in industry arises from driving 
vehicles, such as tractors or fork lift trucks, over rough 
terrain or uneven fl oors. It is highly unlikely that driving 
vehicles on smooth roads will produce WBV problems. As 
explained earlier, the most common health problem asso-
ciated with WBV is back pain. This pain may well have 
been caused by other activities but WBV will aggravate it. 
The reasons for back pain in drivers include:
➤
poor posture while driving
➤
incorrect adjustment of the driver’s seat
➤
diffi culty in reaching all relevant controls due to poor 
design of the controls layout
➤
frequent manual handling of loads, and
➤
frequent climbing up and down from a high cab.
The regulations require that where there is a likelihood of 
WBV, the employer must undertake a risk assessment. 
The HSE Guidance document, L141, gives detailed 
advice to help with this risk assessment and on estimat-
ing daily exposure levels. Whole-body vibration risks are 
low for exposures around the action value and usually 
only simple control measures are necessary.
The regulations allow a transitional period for the 
limit value until July 2010 for vehicles supplied before 
July 2007.
The measurement of WBV is very diffi cult and may 
only be measured accurately by a specialist competent 
person. If the risk assessment has been made and the 
recommended control actions are in place, there is no 
need to measure the exposure of employees to vibration. 
However, HSE have suggested that employers can use 
the following checklist to estimate whether exposure to 
WBV is high:
1. There is a warning in the machine manufacturer’s 
handbook that there is a risk of WBV
2. The task is not suitable for the machine or vehicle 
being used
3. Operators or drivers are using excessive speeds or 
operating the machine too aggressively
4. Operators or drivers are working too many hours on 
machines or vehicles that are prone to WBV
5. Road surfaces are too rough and potholed or fl oors 
uneven
6. Drivers are being continuously jolted or when going 
over bumps rising from their seats
7. Vehicles designed to operate on normal roads are 
used on rough or poorly repaired roads
8. Operators or drivers have reported back problems.
Value of vibration (m/s
2
) 
2.5 3.5 
5 
7 
10 14 20
Exposure time to reach action value (hours) 
8 
4 
2 
1 
30 min 
15 min 
8 min
Exposure time to reach limit value (hours) 
over 24 
16 
8 
4 
2 
1 
30 min
Table 15.3
The change in exposure times as vibration increase

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