hand arm vibration surveillance
DESCRIPTION
A presentation on preventing vibration white finger and hand arm vibration for workers who use hand held toolsTRANSCRIPT
Introduction to Hand Arm Vibration in anOccupational Setting
Contents• Introduction • What is vibration?• How is vibration measured?• Hand-arm vibration syndrome • Regulations• Control of Vibration at Work Regulations 2005• Employers legal duties• Health surveillance guidance• Further Reading
IntroductionHand-arm vibration (HAV) widespread hazard for employees in many industries and occupationse.g. construction/demolition, mining, quarrying, forestry, shipbuilding/repair, foundries, public utilities, railways and aircraft manufacture
• Percussive tools• Caulking tools• Riveting tools• Road breakers
• Rotary tools• Grinders• Sanders• Burring tools
• Forest and garden tools• Chain saws• Motor mowers
• Others• shoe-pounding machines• Motorcycles handle bars
Introduction• Prolonged and regular exposure to vibration can affect the
operators health• 5,000,000 employees exposed• 2,000,000 employees have clear risk of developing disease (HSE 2005)
• Risks from vibration can be controlled and employees protected • To protect employees and to comply with the Vibration Regulations,
employers need to assess the risks from vibration and control them.
What is vibration?• Vibrations arise when a body oscillates due to external and internal
forces
• the handle of a machine or the surface of a work piece vibrates rapidly
• this motion is transmitted into the hand and arm
What is vibration?
Vibration is defined by the • magnitude - acceleration
(m/s2 r.m.s)• frequency (Hz)
What is vibration?Vibration is measured in three planes:
The axes are dependent on the position of the hand relative to the vibrating object – so should
always be noted
X Y Z
How is vibration measured?• Instrumentation:
• HAV measuring equipment should comply with the EN ISO 8041:2005 specifications for hand-arm vibration measuring equipment
• Calibrate and monitor instrumentation for over-loading (e.g. vibration transducers).
• Measurement method• Methods defined in EN ISO 5349-1:2001• Carefully select mounting method as outlined in EN ISO 5349-2:2001
Hand-arm vibration syndrome• Neurological disorders
• Numbness• Tingling• Loss of manual dexterity
• Vascular disorders• VWF
• secondary Raynaud’s phenomenon
• Musculo-skeletal disorders• Reduced grip strength• Bone disorders
• Other - Carpal tunnel syndrome
Symptoms
Mild HAVS
• Episodic blanching
• Numbness
• Tingling
Severe HAVS• Cyanosis
• Skin necrosis
• Gangrene
A hand during an episode of blanching
Regulations
• Control of Vibration at Work Regulations 2005• European Physical Agents (Vibration) Directive (Directive
2002/44)
• RIDDOR 1995
Control of Vibration at Work Regulations 2005
• Exposure action level (EAV)• ‘Daily amount of vibration exposure above which employers are required to
take certain actions to control exposure’• Greater the exposure level, greater the risk, the more action employers will
need to take to reduce the risk• EAV is 2.5 m/s2 A(8)
• Exposure limit value (ELV)• The ‘maximum amount of vibration an employee may be exposed to on any
single day’• ELV is 5 m/s2 A(8)• It represents a high risk above which employees should not be exposed.
Control of Vibration at Work Regulations 2005
Control of Vibration at Work Regulations 2005
• Employers legal duties:• Assess the vibration risk to employees• Decide if employees are likely to be exposed above the daily EAV
• If yes, introduce programme of controls to eliminate risk
• Provide health surveillance to those regularly exposed above the EAV or at risk
Control of Vibration at Work Regulations 2005
• Decide if employees are likely to be exposed above the daily ELV• If yes, take immediate action to reduce their exposure below the limit value• Refer to publications on strategies to reduce vibration exposure e.g.
alternative work methods, equipment selection, purchasing policy for replacing old tools, work schedules, clothing, workstation design, maintenance.
Employers legal duties:
• Information and training on health risks • Keep a record of risk assessment and control actions• Keep health records for employees under health
surveillance• Review and update risk assessments regularly• Consult employee rep. on proposals to control risk and
provide health surveillance
Control of Vibration at Work Regulations 2005 L140 Guidance
• Part 3: Practical control of vibration exposure and risk• Eliminate vibration exposure in the work process
• Reduce exposure by mechanisation
• Select equipment for reduced vibration exposure
• Manage vibration exposure
• Maintain tools and equipment
• Reduce the level of exposure to the hand
• Reduce the period of exposure
• Gloves and warm clothing
• Information and training for operators and supervisors
• Obtaining competent advice or a consultant
Part 5: Tiered approach to health surveillance for HAVS
Initial or baseline assessment
Simple self-administered questionnaire returned to responsible person or qualified person
Targeted assessment
Qualified person (OHN or doctor)
A presumptive diagnosis can be made
Formal Diagnosis
Doctor
RIDDOR report / fitness to work recommendations
Optional
Standardised tests
Not part of routine health surveillance
Useful for studying progression of disease
Tier 1
Tier 3
No symptoms
Fit to work
If symptoms reported or suffers from relevant vascular or neurological disorder
Annual (screening) questionnaire
Tier 2
3 yearly assessment if no symptoms reported by
questionnaire
Health Surveillance
• Questionnaire screening• Diagnosis
• History of symptoms
• Exclude primary Raynaud’s phenomenon
• Exclude other known causes of secondary Raynaud's phenomenon
• Establish that sufficient vibration exposure has occurred
• NB not helped by smoking
Problems
• Episodic nature of attacks
• Subjective history of symptoms
• Subjective history of vibration exposure
• Primary Raynaud’s phenomenon and other causes of secondary Raynaud’s phenomenon
Solution• Stockholm staging• Griffin scoring
• Objective tests:• Specific• Sensitive
Objective measurement
Vascular tests• Finger systolic blood pressures• Rewarming time
Neurological tests• Thermal thresholds• Vibro tactile thresholds• Clinical tactile threshold tests• Nerve conduction velocity
Multi-Channel Plethysmograph
Finger systolic blood pressure
Channel Temperature Monitor
Finger rewarming test
Vibrotactile thresholds test
Vibrotactile Perception Meter
Thermal thresholds test
Thermal Aesthesiometer
Further Reading
Guidance and advice from the HSE at http://www.hse.gov.uk/vibration/• As part of the package which supports the Control of Vibration at
Work Regulations 2005 the HSE have also produced a calculator to assist in calculating exposures for hand-arm vibration.
Hand-arm vibration at work: A brief guide (INDG175)Guide to using the hand-arm vibration calculatorHand-arm vibration calculator [Excel 48KB] Healthy working lives (Scotland) http://www.healthyworkinglives.com/