Table Of ContentA HANDBOOK ON
OCCUPATIONAL HEALTH PRACTICE
IN THE SOUTH AFRICAN MINING INDUSTRY
Editors
R. Guild, R.I. Ehrlich, J.R. Johnston, M.H. Ross
The Safety in Mines ResearchAdvisory Committee (SIMRAC)
Johannesburg 2001
ACKNOWLEDGEMENTS
Thisbookistheresultofthecombinedeffortsofmanypeopleandtheeditorsexpresstheirgratitude
towards the following organisations and individuals for their encouragement and assistance during
thecourseoftheproductionofthebook.
(cid:127) ToPaulvdHeeverfortheideas,encouragementandgenesisofthehandbook
(cid:127) To the SIMHEALTH committee members for their vision in commissioning the book and for
constructiveadvice
(cid:127) To the many authors, all busy professionals, for their contributions of source material and for
copingwithnumerousdeadlines
(cid:127) To the external reviewers who gave of their time and expertise in providing comment and
constructivecriticismofthemanuscripts
(cid:127) TotheSIMPROSSpersonnelwhoprovidedongoingadministrativeassistance
(cid:127) ToSIMRACforfundingthehandbook
(cid:127) Finally,wethankthemanypeopleconcernedwiththepracticeofoccupationalhealthinthemining
industryandwiththequalityoflifeofworkingminersandex-miners,whogaveearlyadviceand
encouragedthisendeavour.Wehopethatthehandbookmeetstheirexpectations
PhotographsonthecovercourtesyofPalaboraMiningCompanyLimitedandtheChamberofMines.
PublishedbyTheSafetyinMinesResearchAdvisoryCommittee(SIMRAC)
23JorissenStreet,BraamfonteinCentre,Braamfontein2001.
ThispublicationiscopyrightundertheBerneConvention.IntermsoftheCopyrightActNo.98of
1978, no part of this publication may be reproduced or transmitted in any form or by any means,
electronic or mechanical, including photocopying, recording or by any information storage and
retrievalsystems,withoutpermissionfromSIMRAC.
Firstprinting2001
ISBN1-919853-02-2
Repro&PrintbyCredaCommunications
FOREWORD
Thepublicationofthisbookcouldnothavebeenmoreappropriatelytimed.Withinthelastmonth,the
MineHealthandSafetyCouncilapprovedaraftofoccupationalhygieneregulationsandguidelines
that will shortly be presented to the Minister of Minerals and Energy for promulgation. These
regulationsandguidelinesconcernoccupationalhygienepractice,reportingofworkplaceexposures,
respiratoryprotectiveequipment,airbornepollutants,thermalstressandnoise.Theyarethemining
equivalentsofthehazardouschemicalsubstancesandotheroccupationalhygienerelatedregulations
under the Occupational Health and SafetyAct of 1993 (OHSA), and they complete the regulatory
frameworkforsafeguardingthehealthofworkersemployedinSouthAfricanmines.
Theroadleadingtothispointhasbeenlongandarduous,fraughtwithtensionandstruggle,andthe
deaths and disability of too many miners. Although the link between exposure in mines and
occupationaldiseasehasbeenwelldocumentedforoveracentury,untilrecentlylittlewasdoneto
appropriatelyquantifyandcontrolsuchexposures.Averagedustlevelshaveinappropriatelyservedas
a proxy for personal exposure.Airborne substances, other than silica and asbestos, have received
scantattentionandhavebeenerroneouslydismissedas‘‘nuisancedust’’.Legislativechanges,starting
withtheOHSAandCompensationforOccupationalandInjuryDiseasesActof1993,markedthestart
ofanewerainwhichoccupationalhealthandtheworkenvironmentareexplicitlyaddressedinlaw.
TheCommissionofEnquiryintoOccupationalHealthandSafetyintheMiningIndustry,whichsat
in1994,andthepromulgationoftheMineHealthandSafetyActof1996achievedthesameforthe
miningsector.
Today, the owners and operators of many factories and mines recognise that productive work
environmentsaresafeandfreefromhealthhazards.SouthAfricanchemicalandminingcompanies
thatcompeteintheglobalmarkethaverecognisedthathighstandardsofhealthandsafetyarevital
for staying in business. Nonetheless, available occupational injury and disease data illustrate that
SouthAfricanworkplacesarefarfromideal.Muchmoremustbedonetoprotectthehealthandsafety
of workers as well as communities exposed to hazards emanating from workplaces. In the mining
sector,despitegapsindata,itiswidelyacceptedthattheburdenofoccupationaldiseasesonworkers
andtheircommunitiesisnowgreaterthanoccupationalinjuries.Thisassessmentisastoundinggiven
thattherateandseverityofinjuriesinourminesareunacceptablyhigh.
Ihavenodoubtthatthisbookrespondstoaneedforguidanceonbreakingwiththepast.Whileour
historicpreoccupationswiththerecognitionofoccupationaldiseaseandthecompensationofworkers
havevalueintheirownright,wemustfocusonprevention.
Fine minds, engaged at the cutting edges of the legal, occupational medicine and occupational
hygiene professions, have edited and written the various chapters of this book. All have applied
themselvestosettingout,inapracticalformat,fundamentalandbestpractice.Thebookcutsabroad
swathethroughgovernance,managementandauditing,hazardidentificationandriskassessment,to
specifictopicssuchasairpollutants,lungdisease,noise,vibrationandheat.Itexemplifieswhatthe
Safety in Mines ResearchAdvisory Committee has to offer to the industry. It is my hope that the
wealthofexperiencecapturedherewillserveasanup-to-dateresourceformanagersandpractitioners
chargedwithgivingeffecttoourlegislation.
MayHermanus
ChiefInspectorofMines
October2001
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THEEDITORS
DrRGuild
OccupationalHealthandSafetyConsultant
Haggis Guild is Managing Director of Advantage Consulting in Johannesburg. The company
providesoccupationalhealthservicestominingandchemicalorganisationsthatencompasscorporate
governance, strategic planning, policy development, health risk assessment and management,
information systems and data analysis, quality improvement and related areas. Dr Guild originally
qualified as a medical practitioner and then earned postgraduate degrees in occupational health
(DOH)andbusiness(M.B.A.)fromtheUniversityofWitwatersrand.Hehas20yearsexperienceof
health,safetyandenvironmentalmanagementwithintheminingandmineralsindustryofwhich15
yearshavebeeninseniormanagementpositions,including10yearsinthecorporateenvironment.
Prof.R.I.Ehrlich
SpecialistinPublicHealthMedicineandOccupationalHealth
Rodney Ehrlich is currently Associate Professor in the Department of Public Health and Primary
HealthCare,UniversityofCapeTown.HeisalsoAdjunctAssociateProfessorintheDepartmentof
CommunityandPreventiveMedicine,MountSinaiSchoolofMedicine,NewYork.Hehastraining
in economics, medicine, epidemiology and occupational health. He has extensive experience in
treating occupational disease, including occupational lung disease in ex-miners, and in conducting
medical surveillance of workers exposed to workplace hazards. He has served as advisor to the
MinistersofHealthandLabouronoccupationalhealthandhascontributedtopolicyandlegislation
intheareasofhazardoussubstancesandoccupationalhealthservices.Hisrecentresearchactivities
have covered lung function testing in the mining industry, pneumoconiosis in gold miners, the
compensationsystemforoccupationaldiseaseandtheimpactoftuberculosisonHIV/AIDS.
Dr.J.R.Johnston
PhysicistandOccupationalHygienist
JohnJohnstonisaphysicistbyprofessionandreceivedhisdoctoratewhileworkingattheInstituteof
OccupationalMedicineandRoyalInfirmaryinEdinburgh,Scotland.Hehasspent26yearsinSouth
Africa in a variety of management, safety, occupational hygiene and environmental roles and was
privilegedtobecomethefirstFellowoftheSouthernAfricanInstituteofOccupationalHygiene.He
iscurrentlyemployedbyAngloAmericanPlatinumCorporationLtd.astheGroupSafety,Healthand
EnvironmentalManager.
Prof.M.H.Ross
SpecialistinPublicHealthMedicineandOccupationalHealth
Mary Ross is currently Occupational Health Programme Manager for SIMRAC and Honorary
Associate Professor in the School of Public Health, University of the Witwatersrand. She is also
Deputy Regional Advisor for the Faculty of Occupational Medicine, UK. She has postgraduate
traininginhealthservicemanagement,epidemiology,tropicaldiseasesandoccupationalhealth.She
has extensive practical and research experience in community and occupational health at a central,
provincialandlocalgovernmentlevelplusindependentconsultancy.Thishasincludedestablishing
and managing occupational health services; providing occupational health advisory services for
expatriateminers;researchonsilicosisintherefractoryindustry;auditoftuberculosisservicesinthe
miningindustry;anddevelopingatrainingmanualontheCOIDActformedicalpractitioners.
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CONTENTS
CHAPTER1 Thelegal,policyandethicalframeworkofoccupationalhealth
practiceintheSouthAfricanminingindustry 1
1.1 Legislativehistory 3
1.2 OverviewofMHSA 3
1.2.1 Thelegalhierarchy 4
1.2.2 Employer’sduties 4
1.2.3 Riskassessmentandhazardcontrol 4
1.2.4 OccupationalHygiene 6
1.2.5 Medicalsurveillance 6
1.2.6 Employee’sdutiesandrights 10
1.2.7 Employeeparticipationinhealthandsafety 11
1.2.8 Tri-partitecommittees 12
1.2.9 Inspectorate 12
1.3 Lawsregulatingdisability 13
1.3.1 Introduction 13
1.3.2 Terminationofemployment 14
1.3.3 Discrimination 14
1.3.4 Affirmativeactionmeasures 14
1.4 Theregulationofmedicaltesting 15
1.4.1 HIV-Testing 15
1.5 BasicConditionsofEmploymentAct 16
1.5.1 Nightwork 17
1.5.2 Pregnancyandmaternity 17
CHAPTER2 OccupationalHealthManagement 19
2.1 Introduction 21
2.2 OccupationalHealthGovernance 21
2.2.1 Settingupthesystem 21
2.2.2 Reporting 23
2.3 Occupationalhealthmanagement 23
2.3.1 Comprehensiveoccupationalhealthpolicies 25
2.3.2 Planningforoccupationalhealth 26
2.3.3 Implementationandoperation 28
2.3.4 Monitoringandcorrectiveaction 31
2.3.5 Managementreview 32
2.4 InternationalOHmanagementsystemstandards 32
2.5 Integratedmanagementsystems 33
2.6 Informationmanagementandreporting 34
2.6.1 Validmeasurementofexposureandoutcomesdata(seeChapter3) 39
2.6.2 Appropriateanalysisandinterpretationofdata(seeChapter3) 39
2.6.3 Validationoflinkagebetweenexposureandoutcome 41
2.7 Auditing 42
2.7.1 Auditprogrammingandplanning 42
2.7.2 Conductingaudits 43
2.8 Guidetoinformationresources 46
CHAPTER3 HazardIdentificationandRiskAssessment 63
3.1 Introduction 65
3.2 Thelegislativeframework 66
3.3 STEPONE:Definetheobjectivesoftheassessment 66
3.4 STEPTWO:Definetheassessmentprocess 67
3.4.1 Thebaselineprocess 67
3.4.2 Issuebasedprocess 68
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3.4.3 Continuousprocess 69
3.5 STEPTHREE:Identifythehazards 70
3.5.1 Biologicaleffectbasisofhazardidentification 70
3.5.2 Epidemiologicalbasisofhazardverification(seeChapter2) 73
3.6 STEPFOUR:Assessexposure 73
3.7 STEPFIVE:Riskrating 74
3.7.1 Establishingaprioritylistforcorrectiveaction 76
3.7.2 Cautionarynotesonriskassessmentinterpretation 77
3.8 STEPSIX:Decidingriskacceptability 77
3.9 Monitoringprogrammes 78
3.9.1 Workplace exposure monitoring methods (Biological sampling not
addressed) 78
3.9.2 Preliminaryconsiderations 79
3.9.3 Samplingstrategy 81
3.9.4 Datacapturingandmanagement 81
3.10 Guidetoinformationresources 81
3.11 SuggestedInternetWebSites 82
CHAPTER4 AirbornePollutants 85
4.1 Introduction 87
4.2 Typesofairbornepollutants 87
4.2.1 Dusts 87
4.2.2 Fumes 87
4.2.3 Mists 87
4.2.4 Gases 87
4.2.5 Vapours 87
4.3 SpecificEntities 87
4.3.1 Asbestos 87
4.3.2 MineralFibres(synthetici.e.man-made) 88
4.3.3 Biologicalagents 89
4.3.4 BlastingFumes 89
4.3.5 Chlorine 90
4.3.6 Dieselengineexhaustemissions 90
4.3.7 Dust 90
4.3.8 Generalminegases 92
4.3.9 Hydrogencyanide 96
4.3.10 Lead 96
4.3.11 Mercury 96
4.3.12 Refrigerants(AmmoniaandFreons) 96
4.3.13 Solventvapours 97
4.3.14 Weldingfumes 98
4.4 OccupationalExposureLimits(OELs) 98
4.4.1 OEL_TWA 98
4.4.2 OEL_STEL 98
4.4.3 OEL-C 98
4.4.4 Listsoflimits 99
4.5 AssessmentofcompliancewithOELs 99
4.5.1 Analyticalmethods 99
4.5.2 Samplingstrategies 99
4.5.3 Airbornedust 102
4.5.4 Gasesandvapours 107
4.5.5 Dieselexhaustemissions 112
4.5.6 Weldingfumes 113
4.5.7 Evaluationofresults 114
4.6 Testingforflammablegases 115
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4.7 Controlofairbornepollutants 116
4.8 Guidetoinformationresources 118
CHAPTER5 OccupationalLungDisease 119
5.1 Introduction 121
5.1.1 Definitionofoccupationallungdisease 121
5.1.2 Importance of occupational lung disease in the SouthAfrican mining
industry 121
5.2 Theoccupationallungdiseases 122
5.2.1 Mineraldustdisease(pneumoconiosis) 122
5.2.2 Silicosis 123
5.2.3 Silicotuberculosis 126
5.2.4 Coalworkers’pneumoconiosis(CWP) 126
5.2.5 Asbestosrelateddiseases 128
5.2.6 Chronicobstructivepulmonarydisease(COPD) 130
5.2.7 Lungcancer 131
5.2.8 Scleroderma/progressive systemic sclerosis (PSS) and rheumatoid
arthritis 132
5.2.9 Miscellaneousmineraldustdiseases 132
5.2.10 Occupational asthma and Reactive Airways Dysfunction Syndrome
(RADS) 133
5.2.11 Inhalationinjuriesandasphyxia 134
5.3 Legalframeworkforpreventionandcompensationofoccupationallungdisease 136
5.4 Medicalsurveillance 137
5.4.1 PurposeofmedicalsurveillanceasmandatedbyMHSA 137
5.4.2 Employeeeducationandmedicalsurveillance 138
5.4.3 MedicalsurveillanceforpneumoconiosisandCOPD 138
5.4.4 Medicalsurveillanceforoccupationalasthma 139
5.4.5 Medical surveillance for mesothelioma, lung cancer and Progressive
SystemicSclerosis(PSS) 139
5.4.6 Data management and reporting responsibilities as part of medical
surveillance 139
5.4.7 Respiratoryquestionnaires 141
5.4.8 ChestRadiology 141
5.4.9 Lungfunctiontesting 143
5.5 Guidetoinformationresources 144
5.5.1 Officialreports 144
5.5.2 Officialregulationsandguidelines 144
5.5.3
CHAPTER6 TuberculosisandAssociatedDiseases 153
6.1 Introduction 155
6.1.1 HistoryofTBontheSouthAfricangoldmines 155
6.1.2 Thecurrentepidemic 155
6.1.3 Legislativeframework 157
6.2 EpidemiologyofTB 158
6.2.1 TBinfection,latencyanddisease 158
6.2.2 RelationshipbetweenTBinfectionandTBdisease 159
6.2.3 FactorsdeterminingtheincidenceofTBinacommunity 159
6.3 TBcontrolintheminingindustry:backgroundandprinciples 162
6.3.1 CurrentstateofTBcontrol 162
6.3.2 Promptdiagnosisandtreatmentofinfectiouscases 162
6.3.3 PreventingtheemergenceofdrugresistantTB 163
6.3.4 Comprehensivepreventivestrategy 163
6.3.5 GuidelinesforaTBcontrolprogramme 164
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6.4 DiagnosisofTB 166
6.4.1 Symptoms 166
6.4.2 Bacteriology 167
6.4.3 Chestradiography 168
6.4.4 CriteriafordiagnosisandclassificationofTB 168
6.4.5 ClinicalandradiologicalfeaturesofHIVassociatedTB 169
6.5 TreatmentofTB 169
6.5.1 Casedefinitions 169
6.5.2 Treatmentregimens 170
6.5.3 In-patientandambulatorycare 170
6.5.4 Adherencetotherapy 170
6.5.5 Missedtreatment 170
6.5.6 Monitoringresponsetotreatment 170
6.5.7 Treatmentoutcomes 171
6.5.8 Specialtreatmentsituations 172
6.5.9 NotificationtotheDepartmentofHealth 173
6.6 Occupationalissues 173
6.6.1 Reporting 173
6.6.2 Sickleaveandcompensation 173
6.6.3 Leave 174
6.6.4 Terminationofemploymentcontract 174
6.6.5 Nosocomial(‘‘hospitalacquired’’)TB 174
6.7 TBcontrolprogrammeevaluation 175
6.8 OtherinterventionstoreducetheincidenceofTB 175
6.8.1 Dustcontrol 175
6.8.2 Housing 176
6.8.3 Isoniazidpreventivetherapy(IPT)forTB 176
6.8.4 HIVpreventionandcare 178
6.8.5 Vaccination 180
6.9 Nontuberculousmycobacterial(NTM)disease 180
6.9.1 CausesandincidenceofNTMdisease 180
6.9.2 HIV-associatedNTMdisease 182
6.9.3 Diagnosticcriteria(casedefinitions) 182
6.9.4 Treatment 182
6.9.5 Controlmeasures 183
6.9.6 Legalconsiderations 183
6.9.7 Overviewofbestpractice 183
6.10 Guidetoinformationresources 183
6.10.1 Reading 183
6.10.2 Internetresources 184
CHAPTER7 NoiseandVibration 193
7.1 Introduction 195
7.2 Noise 195
7.2.1 Extentofproblem 195
7.2.2 Legalresponsibilitiesofemployersandworkers 195
7.2.3 Quantifying noise and exposure levels for risk assessment and
occupationalhygienemonitoring 196
7.2.4 Riskmanagementforthenoisehazard 197
7.3 Vibration 211
7.3.1 Extentofproblem 211
7.3.2 Definitions 211
7.3.3 Wholebodyvibration(WBV) 212
7.3.4 Handarmvibration(HAV) 214
7.4 Guidetoinformationresources 218
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CHAPTER8 Heat 231
8.1 Introduction 233
8.2 Extentandconsequencesofheatstress 233
8.2.1 Safetyandaccidents 233
8.2.2 Health 233
8.2.3 Productionandproductivity 234
8.3 Originsofheatstressanddefinitions 234
8.3.1 Heatstressandstrain 234
8.3.2 Heatbalance 234
8.3.3 Metabolicheatproductionanddissipation 235
8.3.4 PhysicalworkloadsinSouthAfricanmines 236
8.3.5 Environmentalheatloads 237
8.4 Determinantsofworkinheat 237
8.4.1 Workcapacity 238
8.4.2 Endurancefitness 238
8.4.3 Nutritionandhydration 238
8.4.4 Age 238
8.4.5 Gender 238
8.4.6 Bodycompositionanddimensions 239
8.4.7 Heatacclimatisation,heattoleranceandheatintolerance 239
8.5 Heatdisorders 239
8.5.1 Skindisorders(seeChapter13) 240
8.5.2 Heatcramps 240
8.5.3 Heatexhaustion 241
8.5.4 Heatstroke 242
8.6 Heatstressmanagement 245
8.6.1 Heatstressindices 247
8.6.2 Purpose-developedprogrammes 248
8.7 Legislationandstandards 251
8.7.1 Internationalpractice 251
8.7.2 Localpractice 251
8.7.3 Legislationversusstandards 252
8.8 Guidetoinformationresources 252
CHAPTER9 ChemicalHazards 257
9.1 Introduction 258
9.2 Commonchemicalhazardsintheminingindustry 259
9.2.1 SouthAfricancommodityproductiondata 259
9.2.2 Chemicalinventories 260
9.2.3 Genericclassifications 262
9.2.4 Exposuredata 263
9.2.5 Undergroundoperations 265
9.2.6 Surfaceoperations 266
9.3 Adversehealthoutcomesfromexposuretochemicals 270
9.3.1 Factorsdetermininghazardpotential 270
9.3.2 Fateofchemicalsenteringthebody 271
9.3.3 Mechanismsofdiseasecausation 271
9.3.4 Healtheffectsonspecificbodysystems 273
9.4 Assessmentandmonitoringofexposuretochemicalhazards 276
9.4.1 Advantagesanddisadvantagesofbiologicalmonitoring 276
9.4.2 Samplingstrategiesforbiologicalmonitoring 276
9.4.3 Qualitycontrol 277
9.4.4 Interpretingbiologicalmonitoringresults 278
9.4.5 Ethicalconsiderations 278
9.4.6 Workernotificationprogrammes 278
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9.5 Medicalsurveillanceandcasemanagement 279
9.5.1 Objectives 279
9.5.2 Developingamedicalsurveillanceprogramme 279
9.5.3 Testsusedinmedicalsurveillance 280
9.5.4 Typesofmedicalexaminations 281
9.5.5 Workernotificationprogrammesandreportingresults 281
9.5.6 Proceduresindealingwithabnormalresults 281
9.5.7 Auditandhealthinformationsystems 282
9.6 Chemicalcontrol 282
9.6.1 Needforoccupationalhygieneandmedicalexpertise 282
9.6.2 Newprocessdesigns 282
9.6.3 Training 283
9.6.4 LabellingandMaterialSafetyDataSheets 283
9.6.5 Auditandchemicalchecklists 283
9.6.6 Transport 283
9.6.7 Industrycodesandstandards 284
9.6.8 Hazardoussubstancesmanagementprocedures 284
9.7 Guidetoinformationresources 291
9.7.1 Internetresources
CHAPTER10 IonisingRadiation 295
10.1 Introduction 300
10.2 Radioactivityandionisingradiation 300
10.3 Healtheffectsofionisingradiation 300
10.3.1 DeterministicEffects 300
10.3.2 StochasticEffects 301
10.4 Radiationprotectionstandards 302
10.5 Occupationalradiationexposuresintheminingindustry 303
10.6 Thelegalframework 305
10.7 Monitoringofexposurelevels 305
10.7.1 Monitoringforoperationalcontrol 305
10.7.2 Monitoringfortheassessmentofoccupationalexposuresanddoses 305
10.7.3 Monitoringmethods 306
10.7.4 Biologicalmonitoring 307
10.8 Healthsurveillance 307
10.9 Engineeringandadministrativecontrolmeasures 307
10.9.1 Basicprinciples 307
10.9.2 Controlofradonunderground 307
10.9.3 Controlmeasuresinoreprocessingplant 308
10.9.4 Personalprotectiveequipment 308
10.9.5 Personalhygiene 308
10.9.6 Jobrotation 308
10.10 Guidetoinformationresources 308
10.11 Appendices 310
CHAPTER11 Ergonomics 315
11.1 Introduction 317
11.2 TheNatureandScopeofErgonomics 317
11.2.1 Definitionofergonomics 317
11.2.2 Theobjectivesofergonomics 318
11.2.3 Interdisciplinarynatureofergonomics 318
11.2.4 Ergosystem 318
11.3 Ergonomics-relatedHazardsintheWorkplace 320
11.3.1 Basicergonomicconsiderations 320
11.3.2 ErgonomicsRiskFactors 321
11.3.3 Synergismofriskfactors 322
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