L141: Whole-Body Vibration Control

What is L141?

L141 is the HSE's Approved Code of Practice (ACOP) and guidance for controlling whole-body vibration (WBV) under the Control of Vibration at Work Regulations 2005. It provides detailed guidance on protecting workers from the health risks of operating vehicles, mobile machines, and other equipment that transmits vibration through the seat or feet.

Whole-body vibration occurs when workers sit or stand on vibrating surfaces, typically in vehicles and mobile machinery. Long-term exposure is associated with back pain and spinal disorders. L141 explains how to assess vibration exposure, what the legal limits mean, and how to prevent harm through equipment selection, workplace design, and good practice.

The guidance applies to any work where employees are exposed to whole-body vibration, including driving trucks, operating tractors, working on construction machines, and using industrial vehicles.

Who Needs This Document?

L141 is essential for:

• Haulage and logistics companies with HGV drivers
• Construction companies operating excavators, dumpers, and rollers
• Agricultural businesses using tractors and farm machinery
• Quarrying and mining with mobile plant
• Forestry operations using forwarders and harvesters
• Warehouse and distribution with forklift operators
• Bus and coach operators with professional drivers
• Rail industry with train and tram operators
• Shipping and ports with crane and straddle carrier operators
• Any employer with workers operating vehicles or mobile machinery

Key Topics Covered

What is Whole-Body Vibration?

Whole-body vibration is mechanical vibration transmitted to the whole body through:

Seated operators:

• Vehicle seats in trucks, buses, and trains
• Tractor and agricultural machinery seats
• Construction equipment seats (excavators, loaders)
• Forklift truck seats
• Industrial vehicle seats

Standing operators:

• Platform surfaces on machinery
• Floors of moving vehicles
• Vibrating production platforms

Common sources:

• Heavy goods vehicles (HGVs)
• Tractors and agricultural machinery
• Construction plant (excavators, dumpers, dozers, rollers)
• Forklift trucks
• Quad bikes and ATVs
• Helicopters
• Off-road vehicles

Health Effects

L141 describes the health risks from WBV exposure:

Back pain and spinal damage:

• Low back pain is the primary concern
• Degenerative changes to the spine
• Herniated (slipped) discs
• Early degeneration of lumbar spine

Contributing factors:

• WBV combined with poor posture
• Twisting while seated
• Getting in and out of vehicles
• Manual handling tasks
• Shocks and jolts

Other reported effects:

• Digestive problems
• Effects on female reproductive health
• General discomfort and fatigue

Risk factors:

• Duration and intensity of exposure
• Quality of seat and suspension
• Terrain and surface conditions
• Individual susceptibility
• Additional physical demands of job

Exposure Limits

L141 explains the Regulations' exposure values:

Exposure is measured as an 8-hour time-weighted average A(8). Both the vibration magnitude of the machine and the daily exposure time affect the result.

For comparison - typical vibration magnitudes:

• Modern truck on smooth road: 0.3-0.5 m/s²
• Forklift on smooth floor: 0.5-0.8 m/s²
• Tractor on rough ground: 0.8-1.5 m/s²
• Dumper truck off-road: 1.0-2.0 m/s²

Risk Assessment

L141 guides employers through WBV risk assessment:

Identify exposure:

1. Which jobs involve operating vehicles or mobile machinery?
2. Which machines and vehicles are used?
3. How long do workers operate them?
4. What are the operating conditions?

Estimate exposure:

1. Use manufacturer vibration data
2. Consider actual operating conditions
3. Apply appropriate multipliers for terrain
4. Calculate daily exposure A(8)

Evaluate risks:

1. Compare exposures against EAV and ELV
2. Consider individual factors
3. Identify existing controls
4. Determine additional measures needed

Record and review:

1. Document the assessment
2. Communicate findings to workers
3. Review when circumstances change
4. Update regularly

Controlling Exposure

The hierarchy of WBV control:

1. Eliminate or reduce at source:

• Choose low-vibration machines
• Maintain vehicles properly
• Improve road and work surfaces
• Use remote operation where possible

2. Limit exposure time:

• Job rotation between operators
• Schedule breaks from driving
• Limit daily driving hours
• Plan routes to minimise rough terrain

3. Select appropriate equipment:

• Vehicles designed for the task
• Quality seats with effective suspension
• Cab suspension where available
• Appropriate tyres for conditions

4. Maintain equipment:

• Regular seat maintenance
• Suspension systems serviced
• Tyre pressure management
• Address worn components promptly

5. Improve workplace:

• Repair potholes and rough surfaces
• Grade haul roads regularly
• Remove obstacles causing jolts
• Provide smooth loading areas

6. Training and information:

• Train operators in good practice
• Adjust seats properly
• Report problems
• Understand health risks

Seat Selection and Adjustment

The seat is critical for WBV control:

Seat features:

• Suspension matched to operator weight
• Appropriate travel range for terrain
• Horizontal and vertical adjustment
• Lumbar support
• Easy adjustment controls

Proper adjustment:

• Set suspension for operator weight
• Position for comfortable reach
• Adjust mirrors to avoid twisting
• Check adjustment at start of shift

Maintenance:

• Service suspension regularly
• Replace worn components
• Check for seat damage
• Ensure adjustments work

Health Surveillance

Health surveillance may be appropriate:

When health surveillance is needed:

• Workers regularly exposed at or above EAV
• Where there is identifiable disease related to exposure
• Likelihood that disease may occur under work conditions
• Valid techniques available for detection

Health surveillance approaches:

• Pre-employment health questionnaires
• Periodic health questionnaires
• Clinical assessments where indicated
• Individual fitness assessments

Responding to health issues:

• Reassess work activities
• Reduce or remove exposure
• Review control measures
• Consider job modifications

Information and Training

Workers must receive:

• Information on WBV health risks
• Results of risk assessments
• Findings of health surveillance
• How to minimise exposure
• How to recognise and report symptoms
• Proper seat adjustment
• Importance of good posture

Legal Status

L141 is an Approved Code of Practice. Following its guidance is the clearest route to compliance with the Control of Vibration at Work Regulations 2005. Failure to follow the ACOP can be cited as evidence of non-compliance in enforcement proceedings.

Why It Matters

Back pain is a major occupational health issue:

The Scale of the Problem

• Back pain is one of the most common causes of sickness absence
• Professional drivers have elevated rates of back problems
• Operators of construction and agricultural machinery at increased risk
• Costs UK industry hundreds of millions annually

Impact on Workers

• Chronic pain - persistent discomfort affecting daily life
• Mobility problems - difficulty with normal activities
• Loss of income - unable to continue in driving work
• Need for treatment - physiotherapy, surgery, medication
• Early retirement - forced out of occupation prematurely

Consequences for Employers

• Sickness absence - significant lost working days
• Civil claims - compensation for back injuries
• Criminal prosecution - failure to control exposure is an offence
• Driver shortages - losing experienced operators
• Replacement costs - recruiting and training new staff

Prevention is Achievable

L141 provides the framework to prevent WBV harm:

• Select appropriate vehicles and machinery
• Ensure seats are suitable and maintained
• Improve work surfaces
• Limit daily exposure times
• Train operators in good practice

Practical Control Measures

Warning Signs

Workers should report:

• Persistent back pain
• Pain radiating to legs
• Stiffness after driving
• Numbness or tingling
• Difficulty with normal activities
• Pain worsening over time

Early reporting allows early intervention and prevents serious damage.

Calculating Exposure

Simple exposure points system:

Points = Vibration magnitude squared x Hours exposed

100 points = Exposure Action Value 500 points = Exposure Limit Value

This simplified system helps with initial screening. Use HSE calculator for accurate assessments.

Key Compliance Steps

1. Identify all WBV exposure - which workers, which machines, how long
2. Assess vibration levels - manufacturer data, measurements, typical values
3. Calculate daily exposures - compare against EAV and ELV
4. Implement controls - equipment, workplace, work organisation
5. Provide information and training - operators understand risks and controls
6. Consider health surveillance - where appropriate
7. Maintain equipment - seats, suspensions, surfaces
8. Review regularly - update assessment when things change

Further Resources

• Control of Vibration at Work Regulations 2005↗
• HSE Whole-body vibration web pages↗
• HSE Whole-body vibration guidance↗
• HSE Whole-body vibration calculator↗

This page summarises the ACOP L141. For full legal compliance, obtain and read the complete document from HSE. This summary is not a substitute for professional advice or the full ACOP text.