Isom Havs 23.03.07

Control of vibration at workControl of vibration at work

Dr Peter Noone,Dr Peter Noone,

Consultant Occupational Physician, Consultant Occupational Physician,

VibrationVibration

“The men call the condition ‘dead fingers’and it The men call the condition ‘dead fingers’and it is a good name, for the fingers do look like is a good name, for the fingers do look like those of a corpse, a yellowish-greyish white those of a corpse, a yellowish-greyish white and shrunken. There is a clear line of and shrunken. There is a clear line of demarcation between the dead part and the demarcation between the dead part and the normal part.”normal part.”

““they could not tell a dime from a nickel they could not tell a dime from a nickel without looking at it”without looking at it”

ControlControl

There are few circumstances where control is not reasonably practicable,

Control often leads to better quality and increased productivity,

Investment for the future.

Hand-Arm Vibration Syndrome: HistoryHand-Arm Vibration Syndrome: History

1862 - Primary Raynaud's phenomenon 1862 - Primary Raynaud's phenomenon (Raynaud's Disease) identified by Dr Maurice (Raynaud's Disease) identified by Dr Maurice Raynaud. Raynaud.

1911 - Secondary Raynaud's phenomenon first 1911 - Secondary Raynaud's phenomenon first linked to use of pneumatic tools. linked to use of pneumatic tools.

The use of power tools and machines became The use of power tools and machines became widespread with development of electrical widespread with development of electrical power and internal combustion engine. power and internal combustion engine.

1975 - Taylor-Pelmear scale published allowing 1975 - Taylor-Pelmear scale published allowing consistent assessment. consistent assessment.

HistoryHistory

1930’s & `1940’s: iron foundries 1930’s & `1940’s: iron foundries (Seyring(Seyring); ); riveters riveters (Hunt(Hunt); electrically powered high ); electrically powered high speed rotating hand tools (speed rotating hand tools (Telford et alTelford et al); ); grinding wheels (grinding wheels (Agate and DruetAgate and Druet),),

1960’s & 70’s; petrol-powered chain saws 1960’s & 70’s; petrol-powered chain saws in forestry work (Finland, Scotland, in forestry work (Finland, Scotland, Japan).Japan).

Alice Hamilton, the year she graduated from medical school, 1893The Schlesinger Library, Radcliffe Institute, Harvard University

Bedford, Indiana, 1918:

". . .the trouble seems tobe caused by thevibrations of the tool, andcold. If these featurescan be eliminated thetrouble can be decidedlylessened.".

Alice Hamilton, MD .

1978 repeat of the Alice Hamilton study inBedford, prevalence of HAVS=80%= same as 1918 result, nothing changed.

HAVS HistoryHAVS History

1987 - the Stockholm workshop revised the Taylor-1987 - the Stockholm workshop revised the Taylor-Pelmear scale that:Pelmear scale that: divided the condition into two parts - vascular and divided the condition into two parts - vascular and

neurological;neurological;

looked at each hand separately;looked at each hand separately;

discounted seasonal variations in symptomsdiscounted seasonal variations in symptoms

1992 - The Supply of Machinery (Safety) Regulations 1992 - The Supply of Machinery (Safety) Regulations were introduced which required that risks resulting from were introduced which required that risks resulting from vibration emissions should be reduced to the lowest levelvibration emissions should be reduced to the lowest level

1997 - England - Miners High Court compensation 1997 - England - Miners High Court compensation award £127,000 to 7 miners for HAVS award £127,000 to 7 miners for HAVS

UK HistoryUK History Iron and steel trades insurers agreement- fixed Iron and steel trades insurers agreement- fixed

payment,payment, IIAC –VWF prescribed first 1985 (PD A11),IIAC –VWF prescribed first 1985 (PD A11), 1992 min of 14% disability before entitlement,1992 min of 14% disability before entitlement, HAVS –prescribed 1995,HAVS –prescribed 1995, CTS assoc with HAVS 2004,CTS assoc with HAVS 2004, Compensation of Coal Miners by DTI.Compensation of Coal Miners by DTI. Reports- FOM 1993, evidence based rev 2004.Reports- FOM 1993, evidence based rev 2004. HSE: Control of Vibration at Work Regs 2005, HSE: Control of Vibration at Work Regs 2005,

ACOP.ACOP.

EpidemiologyEpidemiology

MRC survey- 288,000 prevalence of VWF MRC survey- 288,000 prevalence of VWF cases (1997-8), 89% male,cases (1997-8), 89% male,

4,800,000 exposed to HAV at work in UK,4,800,000 exposed to HAV at work in UK,HSE estimates over 2 million workers HSE estimates over 2 million workers

exposed above EAV in UK,exposed above EAV in UK,One million exposed above the ELV,One million exposed above the ELV,3000 IIB claimants per year in UK for VWF 3000 IIB claimants per year in UK for VWF

and vibration associated CTS.and vibration associated CTS.

0

100000

200000

300000

400000

500000

600000

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Who’s at riskWho’s at risk

Mechanisms contributing to Raynaud’s Mechanisms contributing to Raynaud’s phenomenonphenomenon

Wigley F. Raynaud’s Phenomenon. N Engl J Med 2002;347(13):1001-8Wigley F. Raynaud’s Phenomenon. N Engl J Med 2002;347(13):1001-8

Secondary Raynaud’sSecondary Raynaud’s atherosclerosis atherosclerosis cervical rib cervical rib CREST syndrome CREST syndrome dermatomyositis dermatomyositis hyperfibrinogenaemia hyperfibrinogenaemia hypothyroidism hypothyroidism leukaemia leukaemia polyarteritis nodosa polyarteritis nodosa polycythaemia rubra vera polycythaemia rubra vera rheumatoid arthritis rheumatoid arthritis scleroderma scleroderma systemic lupus erythematosus systemic lupus erythematosus the presence of cold haemagglutinins the presence of cold haemagglutinins thoracic outlet syndrome thoracic outlet syndrome thrombo-embolic disease thrombo-embolic disease vasculitis vasculitis vasculopathy in diabetes vasculopathy in diabetes

Secondary Raynaud’sSecondary Raynaud’sDrugs and ToxinsDrugs and Toxins

ββ-Blockers-Blockers

ErgotaminesErgotamines

Clonidine Clonidine

Chemotherapeutic agents Chemotherapeutic agents

Polyvinyl chloride Polyvinyl chloride

CyclosporinCyclosporin

InterferonInterferon

OestrogenOestrogen

NarcoticsNarcotics

CocaineCocaine

NicotineNicotine

Vinblastine,Vinblastine,

methysergidemethysergide

Secondary Raynaud’sSecondary Raynaud’s

Large-artery disease:Large-artery disease: VasculitisVasculitis AtherosclerosisAtherosclerosis Thromboangiitis obliteransThromboangiitis obliterans Embolic diseaseEmbolic disease

Paraproteinemia Paraproteinemia

Hyperviscosity state Hyperviscosity state (e.g., Polycythemia vera)(e.g., Polycythemia vera)

CryoglobulinemiasCryoglobulinemias


NeuropathyNeuropathyCarpal tunnel syndromeCarpal tunnel syndromeThoracic outlet syndromeThoracic outlet syndrome

Environmental agents and injuryEnvironmental agents and injuryCold Stress (Frostbite)Cold Stress (Frostbite)Repetitive occupational stress (hand–arm Repetitive occupational stress (hand–arm

vibration syndrome)vibration syndrome)Hypothenar hammer syndromeHypothenar hammer syndrome


Wrong Diagnosis:Wrong Diagnosis:AcrocyanosisAcrocyanosisCentral Cyanosis Central Cyanosis Chilblains/PernioChilblains/Pernio

The symptoms attributed to the neurological The symptoms attributed to the neurological component of HAVS may arise from some component of HAVS may arise from some

medical conditions.medical conditions.

These include: alcoholic peripheral neuropathy carpal tunnel syndrome (see Hand symptoms) cervical spondylosis (where one root is affected on one side) diabetic peripheral neuropathy hemiplegia multiple sclerosis neurofibromatosis poliomyelitis spinal cord compression syringomyelia

Drug treatment can sometimes cause Drug treatment can sometimes cause neuropathyneuropathy

For example:

chloramphenicol cyclosporine ethambutol gold indomethacin isoniazid metronidazole nitrofurantoin perhexiline phenytoin polymyxin streptomycin vincristine

HAVS: PathophysiologyHAVS: Pathophysiology

1.1. Neural DysfunctionNeural Dysfunction

2.2. Local Acral vaso-dysregulationLocal Acral vaso-dysregulation

3.3. Shear stressesShear stresses

4.4. Blood Viscosity and cell activationBlood Viscosity and cell activation


Neural DysfunctionNeural DysfunctionAutonomic dysfunctionAutonomic dysfunctionReceptor dysfunctionReceptor dysfunctionNerve ending dysfunction.Nerve ending dysfunction.

Local Acral vaso dysregulationLocal Acral vaso dysregulationEndothelial damageEndothelial damageEndothelial dysregulationEndothelial dysregulation


Shear stressesShear stressescause of endothelial damagecause of endothelial damage

Blood Viscosity and cell activationBlood Viscosity and cell activationErythrocyte activationErythrocyte activationPlatelet activationPlatelet activationLeukocyte activationLeukocyte activation

Hand-Arm Vibration Syndrome: Pathophysiology

Stoyneva et al. Current pathophysiological views on vibration-induced Raynaud’s phenomenon. Cardiovascular Research. 2003. 57, 615-624

HAVS Diagnosis

Physical exam:Physical exam: Grip strength, Phalen’s, Tinel’s, Allen’s (compression Grip strength, Phalen’s, Tinel’s, Allen’s (compression

radial, ulnar arteries at wrist), Roo’s tests, Lewis-Prusik radial, ulnar arteries at wrist), Roo’s tests, Lewis-Prusik (nailbed compression), Adson’s (neck rotation & deep (nailbed compression), Adson’s (neck rotation & deep inspiration).inspiration).

Objective tests:Objective tests: cold provocation testing (thermometry), Doppler cold provocation testing (thermometry), Doppler

examination of the upper extremities, electromyography, examination of the upper extremities, electromyography, digital plethysmography and current perception threshold digital plethysmography and current perception threshold studies (CPT). Semmes-Weinstein monofilaments.studies (CPT). Semmes-Weinstein monofilaments.

Bloods:Bloods: CBC, serum electrolytes, creatinine, urea, urinalysis, CBC, serum electrolytes, creatinine, urea, urinalysis,

glucose, ESR, TSH, uric acid, rheumatoid factor, glucose, ESR, TSH, uric acid, rheumatoid factor, antinuclear antibody, cryoglobulins, serum protein antinuclear antibody, cryoglobulins, serum protein electrophoresis.electrophoresis.

Test TOSTest TOS

Other testsOther tests

Hypothenar Hammer Syndrome:Hypothenar Hammer Syndrome:

Results from repetitive blunt trauma to the palm of the Results from repetitive blunt trauma to the palm of the hand, hand,

Repeated trauma over the hypothenar eminence may Repeated trauma over the hypothenar eminence may result from gripping a piece of equipment that is result from gripping a piece of equipment that is intrinsically associated with vibration,intrinsically associated with vibration,

The position of the ulnar artery in the hypothenar The position of the ulnar artery in the hypothenar eminence crossing the hamate bone makes it vulnerable eminence crossing the hamate bone makes it vulnerable to repetitive trauma, to repetitive trauma,

May result in aneurysm formation or ulnar artery May result in aneurysm formation or ulnar artery thrombosis,thrombosis,

The aneurysm occasionally serves as a source for The aneurysm occasionally serves as a source for digital emboli. digital emboli.

Cook RA. Hypothenar Hammer syndrome: a discrete syndrome to be distinguished from hand-arm vibration syndrome. Occupational Medicine 2003;53:320-324

Control of Vibration at Work Control of Vibration at Work Regulations 2005Regulations 2005

Employers have a duties to:

Assess Assess Control Control Information, Instruction and trainingInformation, Instruction and trainingCheck (including health surveillance)Check (including health surveillance)

ISO 5349-1:2001 for HAV andISO 2631-1:1997 for WBV.

RISK ASSESSMENTRISK ASSESSMENT

The purpose of assessment is to enable management of risk,

An assessment is adequate if it provides enough information to enable you to take the most appropriate action.

Helps to target the highest exposure processes (biggest gain)

Do you have a problem?Do you have a problem?

Do employees:Do employees: complain of tingling and numbness in hands or fingers after using complain of tingling and numbness in hands or fingers after using

vibrating tools? vibrating tools? Hold work pieces, which vibrate while processed by powered machinery Hold work pieces, which vibrate while processed by powered machinery

such as pedestal grinders? such as pedestal grinders? Regularly use hand-held or guided power tools and machines such as: Regularly use hand-held or guided power tools and machines such as:

Concrete breakers, concrete pokers; Concrete breakers, concrete pokers; Sanders, grinders, disc cutters; Sanders, grinders, disc cutters; Hammer drills; Hammer drills; Chipping hammers; Chipping hammers; Chainsaws, brush cutters, hedge trimmers, Chainsaws, brush cutters, hedge trimmers, Powered mowers; Powered mowers; Scabblers or needle guns. Scabblers or needle guns. Hammer action tools for more than about 15 minutes per day; or Hammer action tools for more than about 15 minutes per day; or Rotary and other action tools for more than about one hour per day. Rotary and other action tools for more than about one hour per day.

Do you work in an industry where exposures to vibration are particularly high, Do you work in an industry where exposures to vibration are particularly high, such as construction, foundries, or heavy steel fabrication/shipyards? such as construction, foundries, or heavy steel fabrication/shipyards?

Which jobs and industries are most likely to Which jobs and industries are most likely to involve hand-arm vibration?involve hand-arm vibration?

Jobs with regular, frequent use of vibrating tools/ equipment, Jobs with regular, frequent use of vibrating tools/ equipment, handling of vibrating materials found widely in industries:handling of vibrating materials found widely in industries:

Building and maintenance of roads and railways; Building and maintenance of roads and railways; Construction; Construction; Estate management (eg maintenance of grounds, parks, water Estate management (eg maintenance of grounds, parks, water

courses, road and rail side verges); courses, road and rail side verges); Forestry; Forestry; Foundries; Foundries; Heavy engineering; Heavy engineering; Manufacturing concrete products; Manufacturing concrete products; Mines and quarries; Mines and quarries; Motor vehicle manufacture and repair; Motor vehicle manufacture and repair; Public utilities (eg water, gas, electricity, telecommunications); Public utilities (eg water, gas, electricity, telecommunications); Shipbuilding and repair. Shipbuilding and repair.

What kinds of tools and equipment can What kinds of tools and equipment can cause ill health from vibration?cause ill health from vibration?

Chainsaws; Chainsaws; Concrete breakers/road breakers; Concrete breakers/road breakers; Cut-off saws (for stone etc); Cut-off saws (for stone etc); Hammer drills; Hammer drills; Hand-held grinders; Hand-held grinders; Impact wrenches; Impact wrenches; Jigsaws; Jigsaws; Needle scalers; Needle scalers; Pedestal grinders; Pedestal grinders; Polishers; Polishers; Power hammers and chisels; Power hammers and chisels; Powered lawn mowers; Powered lawn mowers; Powered sanders; Powered sanders; Scabblers; Scabblers; Strimmers/brush cutters. Strimmers/brush cutters.

Exposure LevelsExposure Levels

For hand-arm vibration— the daily exposure limit value is 5 m/s² A(8); the daily exposure action value is 2.5 m/s² A(8),

For whole body vibration—the daily exposure limit value is 1.15 m/s² A(8); the daily exposure action value is 0.5 m/s² A(8),

How do I estimate vibration How do I estimate vibration exposure?exposure?

Need vibration Need vibration emissionemission from the tool(s) from the tool(s)

Also Also timetime of exposure of exposure

Combine to obtain daily exposure Combine to obtain daily exposure A(8)A(8) in in m/sm/s22

Vibration magnitude Vibration magnitude The vibration magnitude, The vibration magnitude, aahvhv, is ascertained using the formula:, is ascertained using the formula:

aahwxhwx, , aahwyhwy and and aahwzhwz are the rms acceleration magnitudes, in m/s2, measured in are the rms acceleration magnitudes, in m/s2, measured in three orthogonal directions, x, y and z, at the vibrating surface in contact with three orthogonal directions, x, y and z, at the vibrating surface in contact with the hand, and frequency-weighted using the weighting Wh.the hand, and frequency-weighted using the weighting Wh.

The definition for the frequency weighting Wh is given in British Standard BS EN The definition for the frequency weighting Wh is given in British Standard BS EN ISO 5349-1:2001.ISO 5349-1:2001.

Where both hands are exposed to vibration, the greater of the two magnitudes Where both hands are exposed to vibration, the greater of the two magnitudes aahv hv is used to ascertain the daily exposure.is used to ascertain the daily exposure.

Daily exposure to vibrationDaily exposure to vibration

where:where:

aahvhv is the vibration magnitude, in m/s is the vibration magnitude, in m/s22;;

T is the duration of exposure to the vibration magnitude T is the duration of exposure to the vibration magnitude aahvhv; and; and

TT00 is the reference duration of 8 hours (28,800 seconds). is the reference duration of 8 hours (28,800 seconds).

Combined operationsCombined operations total daily exposure consists of two or more operations with different total daily exposure consists of two or more operations with different

vibration magnitudes, the daily exposure (vibration magnitudes, the daily exposure (AA(8)) for the combination of (8)) for the combination of operations,operations,

where:where:

nn is the number of individual operations within the working day; is the number of individual operations within the working day;

aahvihvi is the vibration magnitude for operation is the vibration magnitude for operation ii; and; and

TTi is the duration of operation i is the duration of operation ii..

Dose-response curves and Dose-response curves and threshold limitsthreshold limits

are not applicable to all toolsare not applicable to all toolsare derived from chain-saw dataare derived from chain-saw datado not take into account impulsiveness and do not take into account impulsiveness and

high frequency of many tools,high frequency of many tools,All use the same Wh (freq weighting), derived All use the same Wh (freq weighting), derived

Japan in 1960’s, predicts discomfort rather Japan in 1960’s, predicts discomfort rather than pathological change.than pathological change.

Getting realistic vibration dataGetting realistic vibration data

Ask tool supplierAsk tool supplierDatabasesDatabases

http://http://umetech.niwl.se/eng/default.lassoumetech.niwl.se/eng/default.lasso

http://www.las-bb.de/karla/index_.htmhttp://www.las-bb.de/karla/index_.htm

Trade associations, consultancies, Trade associations, consultancies, government,government,

Measurements Measurements (ISO 5349 parts 1 and 2)(ISO 5349 parts 1 and 2)

HAND-ARM VIBRATION EXPOSURE CALCULATOR

Vibration Time to reach EAV Time to reach ELV Exposure Partial Partial

magnitude 2.5 m/s2 A (8) time in min5 m/s2 A (8) time in minduration time in minsexposure partial expexposure

m/s² r.m.s. hours minutes hours minutes hours minutes m/s² A (8) points

Tool or process 1 0 0






Instructions for use: Daily Total

exposure exposure

Enter vibration magnitudes and exposure durations in the white areas. m/s² A (8) points

To calculate, press the Enter key, or move the cursor to a different cell.

The results are displayed in the yelllow areas.

www.hse.gov.uk/vibrationwww.hse.gov.uk/vibration

PointsPoints

100 pointsAction value-

400 points-Limit value-

Limit and action valuesLimit and action values

If A(8) is greater than 5.0 If A(8) is greater than 5.0

m/s² (ELV)m/s² (ELV)

• Take immediate action to reduce Take immediate action to reduce

exposure below ELV,exposure below ELV,• Identify why ELV is exceeded,Identify why ELV is exceeded,• Amend protection and prevention Amend protection and prevention

measures.measures.(2007 or 2010)(2007 or 2010)

If A(8) greater than 2.5 If A(8) greater than 2.5

m/s² (EAV)m/s² (EAV)

• Establish a programme of risk Establish a programme of risk control measures,control measures,

• Introduce a programme of Introduce a programme of health surveillance for those health surveillance for those who remain above the EAV,who remain above the EAV,

• Info & training.Info & training.

(July 2005)(July 2005)

Average latent periods for vibration-induced Average latent periods for vibration-induced

diseases in different occupationsdiseases in different occupations OccupationOccupation Stage of VWFStage of VWF Latency (years)Latency (years)

Foundry workerFoundry worker Tingling Tingling Numbness Numbness BlanchingBlanching

1.8 1.8 2.2 2.2 2.0.2.0.

Shipyard worker Shipyard worker Tingling Tingling Numbness Numbness BlanchingBlanching

9.1 9.1 12.0 12.0 16.816.8

Chain saw operatorChain saw operator NumbnessNumbness 44

GrinderGrinder BlanchingBlanching 13.713.7

Vibration effects on the hand and arm in industry. Edited by A.J. Brammer et al. New York : John Wiley and Sons, 1982.

What we do not knowWhat we do not know We do not know that the Wh in current standards reflects the

relative importance of different frequencies and axes of vibration in producing any specific disorder.

whether the energy-based daily time-dependency inherent in A(8) reflects the relative importance of vibration magnitude and daily exposure duration.

Relation between A(8) and the years of exposure to develop finger blanching, as in appendix to ISO 5349-1 (2001), is not well-founded.

No consensus on, extent of the disorders caused by HTV (e.g. vascular, neurological, muscular, articular, central), or the pathogenesis of any specific disorder caused by HTV, or the roles of other factors (e.g. ergonomic factors, environmental factors, or individual factors).

Acute exposures to HTV cause both vascular and neurological changes analogous to the changes seen in those occupationally exposed to HTV, but we do not yet know how acute changes relate to the chronic disorders.

Hierarchy of controlHierarchy of control

Elimination,Elimination,

Substitution,Substitution,

Engineering control,Engineering control,

Exposure managementExposure management

Information, instruction and trainingInformation, instruction and training

Demolition without vibrationDemolition without vibrationUse hydraulic crushers instead of demolitionUse hydraulic crushers instead of demolition

hammershammers

Elimination by designElimination by design

Eliminating the need for fettling

Pile croppingC(DM)

Piling operationsPiling operations

Old: Pneumatic pickSlow process with exposure to noise,

vibration, dust, heat

SubstitutionSubstitution

•Is it the best tool for the job? (suitability and efficiency)•Ask the tool users if it’s low vibration?•Use manufacturers’ data•Implement purchasing / hiring policy

Choose the right powered hand-tool

Engineering controlEngineering control

JIGS

•Vibration reduction

•Better ergonomics

•Increased productivity

Example – vibration reduced breaker:Example – vibration reduced breaker:

Keep the moil point sharp Break a little at a time, Don’t get jammed Don’t force anti-vibration

handles Stop breaker before pulling

out

Exposure managementExposure management

Specify maximum exposure timesSpecify maximum exposure timesMay need job rotationMay need job rotationNeed to take account ofNeed to take account of

Productivity – what are you asking workers to Productivity – what are you asking workers to do?do?

CommunicationCommunicationSupervisionSupervisionBonus!Bonus!

Reduce Personal RisksReduce Personal Risks MMaintenance - keep tools well maintained EExercise hands during work periods AAlways report any Hand-Arm symptoms SSmoking - don't smoke, especially before using tools UUse the right tool for the job in the right way

(ergonomics) RReport faulty, ineffective or poorly maintained tools EEnsure you keep your hands as warm as possible SShort breaks - multiple short breaks better than long

ones

HEALTH SURVEILLANCE-whenHEALTH SURVEILLANCE-when

Regular exposure above EAV of 2.5 m/s2 A(8),

(or cases of HAVS occurring below EAV),

Baseline ( pre-employment, pre-placement ),

First six months,

Annually thereafter.

(unless accelerated change)

Provide employees withProvide employees withinformation on:information on:

the health effects of HTV; sources of HTV; whether they are at risk, and if so whether the risk is high (above the ELV),

medium (above the EAV) or low; the risk factors (eg the levels of vibration, daily exposure duration, regularity

of exposure over weeks, months and years); how to recognise and report symptoms; the need for health surveillance, how it can help them remain fit for work,

how you plan to provide it, how you plan to use the results and the confidentiality of the results;

ways to minimise risk including: changes to working practices to reduce vibration exposure; correct selection, use and maintenance of equipment; correct techniques for equipment use, how to reduce grip force etc; maintenance of good blood circulation at work by keeping warm and massaging fingers

and, if possible, cutting down on smoking. You should consult your safety or employee representative on your

proposals for training and information.

Why do health surveillance for HAVS?Why do health surveillance for HAVS?

Detection of adverse health effects at an early stage,

Identifying and protecting individuals at increased risk,

Feedback on risk assessment, check effectiveness of control measures,

Prevent progression to disability.

Tiered ProcessTiered Process

Qualified person ( tiers 1,2 & 3),

Responsible person ( tier 2),

Doctor; usually OP ( tier 4),

Competency- FOM approved training course (www.facoccmed.ac.uk)

Health surveillance (TieredHealth surveillance (Tieredapproach)approach)

Level 1 – Pre-placement Questionnaire/leaflet Level 2 – Routine Annual Health Surveillance

(Responsible person) Level 3 – Assessment by Qualified Person

(Grip strength, Purdue Pegboard, Monofilament) Level 4 – Diagnosis by Doctor (Fitness to work,

RIDDOR, IIDB) Level 5 – Standardised Testing

Vascular: CPT, FSBP, Neurological: Vibrotactile Threshold, Thermal Perception

Threshold

HAVS ComponentsHAVS Components

HAVS SN COMPONENT; numbness, tingling, loss of sensation,

VASCULAR; Vibration white finger,

MUSCULOSKELETAL;Pain,stiffness,arthritis,bone cysts, reduced grip strength.

Impairment due to HAVSImpairment due to HAVS

White finger, numbness, tingling PainLoss of tactile sensation in hands (clumsy)Reduced manual dexterityReduced grip strength/cramps Interference with function (ADL & ability to

perform simple tasks)

Staging for Hand-arm Vibration Syndrome Staging for Hand-arm Vibration Syndrome (Taylor-Pelmear System)(Taylor-Pelmear System)

Stockholm (Revised) Hand-arm Vibration Stockholm (Revised) Hand-arm Vibration Syndrome ClassificationSyndrome Classification

Adapted Stockholm Scale (Lawson 2005)Adapted Stockholm Scale (Lawson 2005)

Splitting of Stage 2 Vascular

Early: Frequency of blanching< 3/week Griffin score (5 – 9)

Late: Frequency of blanching> 3/week

Neurological Early: Intermittent symptoms Late : Persistent symptoms > 2 hours Abnormal VTT, TPT, Abnormal Purdue

Standardised TestsStandardised Tests

Used to assess degree of dysfunction Sensorineural Tests:

Vibrotactile Threshold Thermal Perception Threshold (aesthesiometry),

Vascular Test: FSBP – following cooling of the digits ( measures interruption

of blood flow in response to cold) Cold Provocation Test – provides visual evidence of

blanching

PrognosisPrognosis

HAVS with solely sensory symptoms = 20%, Often more disabling.

Vascular symptoms may be reversible following removal from vibrating tools (n=113, 78% improved)

Whole Body VibrationWhole Body Vibration

WBV- Who is at risk?WBV- Who is at risk?

Very little need for concern about WBV in Very little need for concern about WBV in road vehiclesroad vehicles

Some concern for industrial trucksSome concern for industrial trucksparticularly if used on inappropriate surfacesparticularly if used on inappropriate surfaces

Main concern in off-road machinery:Main concern in off-road machinery:agriculture, construction, quarrying, mining, agriculture, construction, quarrying, mining,

forestry, small fast boats, etc.forestry, small fast boats, etc.

WBVWBV 9,000,000 exposed to WBV

Mostly road transport Low risk, simple management

measures

>1,300,000 above the EAV Many still at low risk

>370,000 above 15 m/s VDV see pie chart

<1% exposed above the ELV >20,000–Some activities in

agriculture, mining, quarrying, construction, etc.

What we do not knowWhat we do not know

We are not able to predict the probability of any disorder from the severity of an exposure to WBV.

We do not know whether there is any disorder

specific to WBV, or what disorders are aggravated by exposure to WBV

We do not know the relative importance of vibration and other risk factors in the development of back disorders.

ControlControl

DriverDriver Drive slowly and avoid rough groundDrive slowly and avoid rough ground Provide training (seat and cab adjustment)Provide training (seat and cab adjustment)

VehicleVehicle Right vehicle for the right jobRight vehicle for the right job Maintenance (tyre pressures, seats)Maintenance (tyre pressures, seats)

SiteSite Traffic managementTraffic management Maintain surfacesMaintain surfaces

Holistic approach to lower back painHolistic approach to lower back pain

Many issues with the nature of low back pain:Many issues with the nature of low back pain:

High prevalence in the general populationHigh prevalence in the general population Many causative and influencing factorsMany causative and influencing factors

ErgonomicsErgonomics Manual handlingManual handling etcetc

Symptoms not always synonymous with damageSymptoms not always synonymous with damage No dose-response relationshipNo dose-response relationship

SummarySummary

Start with a fit for purpose assessment of the Start with a fit for purpose assessment of the risk.risk. Simple risk assessmentSimple risk assessment Target high risk processes for controlTarget high risk processes for control

Refine risk assessmentRefine risk assessment Update and maintain controlUpdate and maintain control Information, instruction and trainingInformation, instruction and training Health surveillanceHealth surveillance

HAVS is a preventable diseaseHAVS is a preventable disease

StandardsStandards ISO 5349-1 (2001): Mechanical vibration – Measurement and evaluation of human

exposure to HTV, Part 1 General requirements.

ISO 5349-2 (2001): Mechanical vibration – Measurement and evaluation of human exposure to HTV, Part 2 Practical guidance for measurement at the workplace.

ISO 8662-1 (1988): Hand-held portable power tools – Measurement of vibrations at the handle, Part 1 General,

ISO 8662-3 (1992): Hand-held portable power tools – Measurement of vibrations at the handle, Part 3 Rock drills and rotary hammers,

ISO 8662-4 (1994): Hand-held portable power tools – Measurement of vibrations at the handle, Part 4 Grinders,

ISO 8041 (1990): Human response to vibration – Measuring instrumentation.

ISO 8041 (1993): Technical Corrigendum, Human response to vibration – Measuring instrumentation.

Technology

Isom Havs 23.03.07