OVERVIEW OF INDUSTRIAL OVERVIEW OF INDUSTRIAL HYGIENEHYGIENE

PRINCIPLES OF PRINCIPLES OF EVALUATING WORKER EVALUATING WORKER

EXPOSUREEXPOSURE

UNIVERSITY OF HOUSTON - CLEAR LAKEUNIVERSITY OF HOUSTON - CLEAR LAKE

SPRING 2015SPRING 2015

DEFINITIONDEFINITION

Industrial Hygiene (IH) Industrial Hygiene (IH) is the science is the science devoted to the devoted to the anticipationanticipation, , recognitionrecognition, , measurement, measurement, evaluationevaluation, and , and controlcontrol of of adverse occupational stresses or agents adverse occupational stresses or agents which could cause sickness and impaired which could cause sickness and impaired health among workers and the health among workers and the community. community. Goal of IHGoal of IH (i.e. occupational hygiene) is to (i.e. occupational hygiene) is to promote a safe and healthful work promote a safe and healthful work environment.environment.

OCCUPATIONAL HYGIENEOCCUPATIONAL HYGIENE

The The science and artscience and art of: of:

anticipating, anticipating,

recognizing, recognizing,

evaluating, and evaluating, and

controlling workplace health hazards.controlling workplace health hazards.

PurposePurpose - understand general principles of - understand general principles of evaluating worker exposures. evaluating worker exposures.

IH FOCUSIH FOCUS

1.1. Hazardous agents in workplaceHazardous agents in workplace

2.2. Health effects associated withHealth effects associated with

excessive exposuresexcessive exposures

3.3. Occupational Exposure Limits (OELs)Occupational Exposure Limits (OELs)

for each agentfor each agent

4.4. Workforce organization and staffingWorkforce organization and staffing

5.5. Significant sources of exposure; tasks Significant sources of exposure; tasks and work procedures involvedand work procedures involved

6.6. Control measuresControl measures

IH ELEMENTSIH ELEMENTS

AnticipationAnticipation RecognitionRecognition EvaluationEvaluation ControlControl

GENERAL PRINCIPLESGENERAL PRINCIPLES

Sequence for Sequence for decision–making processdecision–making process Exposure assessment Exposure assessment evaluation by: evaluation by:

qualitative, qualitative, semi-quantitative, or semi-quantitative, or quantitative methods (depends on purpose)quantitative methods (depends on purpose)

Feedback from multiple sourcesFeedback from multiple sources Effective OH program, info collection, Effective OH program, info collection,

analysis, and decision-making are analysis, and decision-making are continuous and simultaneouscontinuous and simultaneous..

ANTICIPATIONANTICIPATIONExpectation of Expectation of potential health hazardspotential health hazards is generally is generally more difficult for the entry-level and inexperienced more difficult for the entry-level and inexperienced OH/IH personnel. OH/IH personnel. Skills generally increase with experience. Skills generally increase with experience. Ability to recognize potential health hazards: Ability to recognize potential health hazards:

- scientific developments, - scientific developments, - new technologies, and - new technologies, and - regulatory requirements, etc.- regulatory requirements, etc.

RECOGNITIONRECOGNITIONRequires knowledge and understanding of: Requires knowledge and understanding of:

- workplace environmental stresses; - workplace environmental stresses; - effects on worker health; - effects on worker health; - processes and control measures; - processes and control measures; - inventory of hazards including: - inventory of hazards including:

- - chemical,chemical, - - biological,biological, and and - - physical hazardsphysical hazards. .

Potential chemical hazards – determination of Potential chemical hazards – determination of toxicitytoxicity and and conditions of useconditions of use. . Collect available information - apply IH principles. Collect available information - apply IH principles.

RECOGNITIONRECOGNITION

Detailed informationDetailed information to be obtained regarding: to be obtained regarding: - hazardous materials used (i.e. - hazardous materials used (i.e.

inventory), inventory),

- type of job operation, - type of job operation,

- worker exposures and patterns, - worker exposures and patterns,

- levels of air contaminants, - levels of air contaminants,

- exposure duration, - exposure duration,

- control measures, etc. - control measures, etc.

RECOGNITIONRECOGNITION

Consult product information - MSDSs. Consult product information - MSDSs.

Develop Develop workplace characterizationworkplace characterization – –

define define “exposure groups” “exposure groups”

for same tasks/similar manner for same tasks/similar manner

(e.g. (e.g. chemical, physical, chemical, physical,

biological hazardsbiological hazards, etc. , etc.

also also ergonomicergonomic considerations). considerations).

EVALUATIONEVALUATION

Involves observation; Involves observation;

monitoring and use of analytical methods required monitoring and use of analytical methods required to detect the to detect the extentextent of exposure; of exposure;

decision-making process for opinion on the decision-making process for opinion on the degree of health hazards and/or stressorsdegree of health hazards and/or stressors; ;

determine determine significancesignificance (e.g. judgment); (e.g. judgment);

extent of potential health hazards based on extent of potential health hazards based on comparisons of environmental measurements comparisons of environmental measurements with current governmental regulations and with current governmental regulations and recommended technical guidelinesrecommended technical guidelines..

EVALUATIONEVALUATION Exposure assessmentExposure assessment: :

initial qualitative method for prioritization; initial qualitative method for prioritization; then, semi-quantitative (i.e. mathematical modeling) then, semi-quantitative (i.e. mathematical modeling) or quantitative (i.e. monitoring) methodologies.or quantitative (i.e. monitoring) methodologies.

Air monitoringAir monitoring for quantitative assessment; for quantitative assessment; breathing zone exposures preferred.breathing zone exposures preferred.

On-going processOn-going process: feedback from multiple info : feedback from multiple info sources; refine exposure estimates; evaluate sources; refine exposure estimates; evaluate control effectiveness; priorities change/modify!control effectiveness; priorities change/modify!

Initially “dangerous trades” vs. varied issues today.Initially “dangerous trades” vs. varied issues today.

EFFECTIVE EVALUATIONEFFECTIVE EVALUATION

Utilize a Utilize a multi-disciplinary approachmulti-disciplinary approach including including knowledge-based technical information. knowledge-based technical information. ContributionsContributions include: occupational hygiene, include: occupational hygiene, chemistry, engineering, health physics, medicine, chemistry, engineering, health physics, medicine, epidemiology, toxicology, and nursing disciplines epidemiology, toxicology, and nursing disciplines as well as management and manufacturing as well as management and manufacturing expertise.expertise.

Integrate knowledge and develop control Integrate knowledge and develop control strategies for potential risk limitation.strategies for potential risk limitation.

Consider Consider team-based effortsteam-based efforts of personnel of personnel including getting expert opinions and other input.including getting expert opinions and other input.

EXPOSURE ASSESSMENTEXPOSURE ASSESSMENT

Control exposures Control exposures Compliance determinations Compliance determinations Program management (i.e. respiratory; Program management (i.e. respiratory;

hearing/noise; medical surveillance, etc.)hearing/noise; medical surveillance, etc.) Epidemiologic studiesEpidemiologic studies Health complaint investigationsHealth complaint investigations Risk assessmentRisk assessment Proposed change evaluations to processProposed change evaluations to process

CONTROLCONTROL

Involves the Involves the reduction of environmental reduction of environmental stressesstresses to: to:

levels that the worker can tolerate without levels that the worker can tolerate without impairment of health or productivity; impairment of health or productivity;

various general control methods employed various general control methods employed for use in an efficient and effective for use in an efficient and effective manner.manner.

CONTROLCONTROL

Defined as the Defined as the adjustment or regulation adjustment or regulation of of an operation to meet a standard or an operation to meet a standard or guideline; guideline;

the reduction or prevention of contaminant the reduction or prevention of contaminant release; and, release; and,

the ability to contain a stressor/hazard. the ability to contain a stressor/hazard.

CONTROL METHODSCONTROL METHODS

EngineeringEngineering – remove the hazard; should – remove the hazard; should be primarily considered.be primarily considered.

AdministrativeAdministrative – reduce exposures through – reduce exposures through scheduling/job rotation; housekeeping; scheduling/job rotation; housekeeping; employee training; not generally favored.employee training; not generally favored.

Personal Protective EquipmentPersonal Protective Equipment (PPE) (PPE) – – use should be secondary to design and use should be secondary to design and implementation of engineering controls.implementation of engineering controls.

ENGINEERING CONTROLSENGINEERING CONTROLS

• SubstitutionSubstitution

• Change in processChange in process

• Source modificationSource modification

• IsolationIsolation

• EnclosureEnclosure

• Wet methodsWet methods

• VentilationVentilation

ADMINISTRATIVE CONTROLSADMINISTRATIVE CONTROLS

EXAMPLESEXAMPLES::-- Arrange work schedules and Arrange work schedules and frequency/duration to limit frequency/duration to limit employee employee exposures.exposures.-- Transfer employees with airborne Transfer employees with airborne exposures at PELs to an exposures at PELs to an environment environment which limits additional exposures.which limits additional exposures.-- Housekeeping; preventive Housekeeping; preventive maintenance.maintenance.

ADMINISTRATIVE CONTROLSADMINISTRATIVE CONTROLS

Administrative controls Administrative controls must be designed: must be designed: by knowledgeable H & S personnel, by knowledgeable H & S personnel, and, used cautiously. and, used cautiously.

Not as satisfactory as engineering controls Not as satisfactory as engineering controls and criticized as a means of spreading and criticized as a means of spreading exposures instead of reduce/eliminate exposures instead of reduce/eliminate personal exposures.personal exposures.

PPEPPE

PPEPPE may be used to protect the worker when not may be used to protect the worker when not feasible to render the work environment safe. feasible to render the work environment safe. Examples: Examples: eye/foot/head protection, gloves, eye/foot/head protection, gloves, respirators, respirators, etc.etc.

Considered a secondary control method to Considered a secondary control method to engineering and administrative controls and engineering and administrative controls and should be used as a last resort.should be used as a last resort.

EFFECTIVE IH PROGRAMEFFECTIVE IH PROGRAM

Applies knowledge to the Applies knowledge to the anticipation and anticipation and recognitionrecognition of health hazards from work of health hazards from work operations and processes, operations and processes, evaluationevaluation and measurement of the and measurement of the magnitude of the hazard based on past magnitude of the hazard based on past experience and study, and experience and study, and controlcontrol of the occupational hazards. of the occupational hazards.

POTENTIAL HAZARDSPOTENTIAL HAZARDS

ChemicalChemical PhysicalPhysical BiologicalBiological ErgonomicErgonomic

CHEMICAL HAZARDSCHEMICAL HAZARDS

HydrocarbonsHydrocarbons SolventsSolvents Oil MistOil Mist Dust (Total and Respirable)Dust (Total and Respirable) Crystalline SilicaCrystalline Silica FormaldehydeFormaldehyde Carbon MonoxideCarbon Monoxide Airborne FibersAirborne Fibers

PHYSICAL HAZARDSPHYSICAL HAZARDS

NoiseNoise RadiationRadiation

-- IonizingIonizing-- Non-ionizingNon-ionizing

LightingLighting Heat/Cold StressHeat/Cold Stress Pressure Extremes Pressure Extremes

BIOLOGICAL HAZARDSBIOLOGICAL HAZARDS

BioaerosolsBioaerosols Surface/Bulk ContaminationSurface/Bulk Contamination TuberculosisTuberculosis Bloodborne PathogensBloodborne Pathogens Indoor Air Quality IssuesIndoor Air Quality Issues

ERGONOMIC HAZARDSERGONOMIC HAZARDS

Musculoskeletal DisordersMusculoskeletal Disorders Cumulative Trauma DisordersCumulative Trauma Disorders Carpal Tunnel SyndromeCarpal Tunnel Syndrome Material Handling/LiftingMaterial Handling/Lifting Workplace Design ConsiderationsWorkplace Design Considerations

OTHER HAZARDSOTHER HAZARDS

Confined SpacesConfined Spaces Waste ManagementWaste Management Lab Health and SafetyLab Health and Safety Emergency PlanningEmergency Planning Etc. . . Etc. . .

EXPOSURE ASSESSMENTEXPOSURE ASSESSMENT

Determination or estimation of the magnitude, Determination or estimation of the magnitude, frequency, duration, and route of exposure.frequency, duration, and route of exposure.

Estimation can be qualitative or quantitative. Estimation can be qualitative or quantitative. Defines exposures that occur or anticipated for Defines exposures that occur or anticipated for

human populations.human populations. Complex task Complex task regarding persons and workplace regarding persons and workplace

exposures to hazardous substances.exposures to hazardous substances.

FIVE STEPS FOR FIVE STEPS FOR EXPOSURE ASSESSMENTEXPOSURE ASSESSMENT

Determine purpose and scope of surveyDetermine purpose and scope of survey Become familiar with process operationsBecome familiar with process operations Perform preliminary/qualitative surveyPerform preliminary/qualitative survey Conduct workplace monitoring (i.e. Conduct workplace monitoring (i.e.

quantitative evaluation)quantitative evaluation) Interpret results.Interpret results. Steps can be consecutive or simultaneous!Steps can be consecutive or simultaneous!

TYPES OF EVALUATIONSTYPES OF EVALUATIONS

Comprehensive exposure assessmentComprehensive exposure assessment to to identify and quantify health hazards identify and quantify health hazards

Assess compliance Assess compliance with regulatory with regulatory standards and/or technical guidelinesstandards and/or technical guidelines

Review exposures Review exposures based on complaints based on complaints Exposure assessment Exposure assessment for medical and for medical and

epidemiological studies epidemiological studies Determine effectiveness Determine effectiveness of engineering of engineering

and/or administrative controls. and/or administrative controls.

COMPREHENSIVE EXPOSURE COMPREHENSIVE EXPOSURE ASSESSMENTASSESSMENT

Primary objectivePrimary objective - acceptability of health hazard - acceptability of health hazard exposures for all workers in occupational settings exposures for all workers in occupational settings or for specific operations such as batch or for specific operations such as batch production, spill response, pilot projects, and production, spill response, pilot projects, and maintenance. maintenance.

Identification and quantification/estimation of Identification and quantification/estimation of exposures to workplace stressors; use of walk-exposures to workplace stressors; use of walk-through survey procedures, and evaluation through survey procedures, and evaluation techniques to estimate employee exposure levels. techniques to estimate employee exposure levels. Use of databases. Use of databases.

COMPLIANCE SURVEYCOMPLIANCE SURVEY

Exposure to stressors are quantified and Exposure to stressors are quantified and evaluated by comparison to published health evaluated by comparison to published health standards, standards, OSHA Permissible Exposure OSHA Permissible Exposure Limits (PELs) Limits (PELs) or technical recommended or technical recommended guidelines such as guidelines such as American Conference of American Conference of Governmental Industrial Hygienists (ACGIH) Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLVs). Threshold Limit Values (TLVs).

Determine Determine compliance vs. non-compliancecompliance vs. non-compliance. .

COMPLIANCECOMPLIANCE

Compliance is acting in accordance with health Compliance is acting in accordance with health and safety regulations.and safety regulations.

Noncompliance is failure to act as above.Noncompliance is failure to act as above. Demonstration of noncompliance requires that an Demonstration of noncompliance requires that an

exposure exceed the standard with an acceptable exposure exceed the standard with an acceptable degree of certainty, usually 95% confidence. degree of certainty, usually 95% confidence.

Therefore, Therefore, maximum risk employees maximum risk employees addressed addressed for comparison. Indicate OH program weakness.for comparison. Indicate OH program weakness.

Standards allow re-evaluation Standards allow re-evaluation related to related to documentation and rigorous statistics regarding documentation and rigorous statistics regarding exposures being under control as an incentive.exposures being under control as an incentive.

COMPLAINT RESPONSECOMPLAINT RESPONSE

EvaluationEvaluation should include interviews, should include interviews, walk-through surveys to obtain necessary walk-through surveys to obtain necessary workplace information.workplace information.

RecognizeRecognize cause of health hazard as cause of health hazard as same or different than noted.same or different than noted.

At conclusion, inform complainant of At conclusion, inform complainant of results to demonstrate that potential results to demonstrate that potential health hazards are seriously considered.health hazards are seriously considered.

MEDICAL AND MEDICAL AND EPIDEMIOLOGICAL STUDIESEPIDEMIOLOGICAL STUDIES Personnel need to Personnel need to understandunderstand worker exposures worker exposures

to evaluate the effect - individually or group.to evaluate the effect - individually or group. Past exposure Past exposure assessed by modeling scheme or assessed by modeling scheme or

on a qualitative, subjective basis.on a qualitative, subjective basis. QuantificationQuantification of past exposures is difficult. of past exposures is difficult. Exposure information Exposure information available for available for

epidemiological studies to relate health effects.epidemiological studies to relate health effects.

CONTROL EFFECTIVENESSCONTROL EFFECTIVENESS

Effectiveness of engineering and Effectiveness of engineering and administrative controls administrative controls assessed either assessed either separately or as part of a comprehensive separately or as part of a comprehensive exposure assessment. exposure assessment.

Example:Example: before and after monitoringbefore and after monitoring related to engineering controls.related to engineering controls.

AdministrativeAdministrative controls by sampling over controls by sampling over time during use of various work practices.time during use of various work practices.

PROCESS OPERATIONSPROCESS OPERATIONS

Physical facility layout Physical facility layout Process description and stepsProcess description and steps Inventory of process stressors/hazards Inventory of process stressors/hazards Employee job classificationsEmployee job classifications Worker health statusWorker health status Control measures in place Control measures in place Past evaluation results Past evaluation results Other associated process hazardsOther associated process hazards

PHYSICAL FACILITY LAYOUTPHYSICAL FACILITY LAYOUT

Understand general facility layoutUnderstand general facility layout Location, terrain, physical arrangementLocation, terrain, physical arrangement Examine facility (i.e. blueprints, drawings, Examine facility (i.e. blueprints, drawings,

diagrams, documents, etc.)diagrams, documents, etc.) Observe ventilation systems along with Observe ventilation systems along with

existing airflow patternsexisting airflow patterns Photographic documentationPhotographic documentation

PROCESS DESCRIPTIONPROCESS DESCRIPTION

InformationInformation obtained through interviews, obtained through interviews, personal/personal/visualvisual observationsobservations, technical , technical process information, and record reviews.process information, and record reviews.

Walk-through survey Walk-through survey is an important is an important methodology to understand, verify, and/or methodology to understand, verify, and/or document; investigate potential sources of document; investigate potential sources of health hazards along with air contaminants health hazards along with air contaminants and physical agents. and physical agents.

POTENTIAL INDUSTRIAL AIR POTENTIAL INDUSTRIAL AIR CONTAMINANTSCONTAMINANTS Welding fumes Welding fumes – metal fumes and oxides, – metal fumes and oxides,

welding rods, coatings, decomposition welding rods, coatings, decomposition products, and products of combustionproducts, and products of combustion

Combustion products Combustion products – CO, NOx, – CO, NOx, particulatesparticulates

Foundry emissions Foundry emissions – Si, oil mist, metals, CO– Si, oil mist, metals, CO SmeltingSmelting – combustion products, metal – combustion products, metal

fumes, SOfumes, SO22, and metals, and metals

POTENTIAL INDUSTRIAL POTENTIAL INDUSTRIAL PHYSICAL AGENTSPHYSICAL AGENTS NoiseNoise – equipment, compressed air, etc. – equipment, compressed air, etc. Ionizing radiation Ionizing radiation - isotopes, machinery, X-- isotopes, machinery, X-

Ray, process controls (levels, thickness) Ray, process controls (levels, thickness) Non-ionizing radiation Non-ionizing radiation – welding, UV energy, – welding, UV energy,

thermal IR sources, radar, microwave, etc.thermal IR sources, radar, microwave, etc. Heat Heat – thermal stresses include furnaces, – thermal stresses include furnaces,

smelting, casting operations, drying ovens smelting, casting operations, drying ovens

STRESSOR INVENTORYSTRESSOR INVENTORY

Hazard/StressorHazard/Stressor listing for identification listing for identification Chemical and physical agentsChemical and physical agents MSDSs; Haz Com (29 CFR 1910.1200)MSDSs; Haz Com (29 CFR 1910.1200) Toxicological information; reference sourcesToxicological information; reference sources Occupational Exposure Limits (OELs) Occupational Exposure Limits (OELs)

e.g. OSHA PELs, ACGIH TLVs, e.g. OSHA PELs, ACGIH TLVs,

NIOSH RELs, AIHA WEELs, NIOSH RELs, AIHA WEELs,

ANSI, NIOSH Pocket GuideANSI, NIOSH Pocket Guide

TOXICITY VS. HAZARDTOXICITY VS. HAZARD

ToxicityToxicity is the capacity of a material to is the capacity of a material to produce injury or harm to living tissue produce injury or harm to living tissue when agent has reached a sufficient when agent has reached a sufficient concentration at certain site in the body. concentration at certain site in the body.

HazardHazard is the probability that this is the probability that this concentration will occur within the body; concentration will occur within the body; affected by many factors related to affected by many factors related to conditions of use, frequency, duration. conditions of use, frequency, duration.

OCCUPATIONAL EXPOSURE OCCUPATIONAL EXPOSURE LIMITS (OELs)LIMITS (OELs)

Regulatory standard Regulatory standard – issued by – issued by governmental body (i.e. OSHA)governmental body (i.e. OSHA)

Voluntary guidelines Voluntary guidelines – published by – published by consensus process (i.e. ACGIH, ANSI); consensus process (i.e. ACGIH, ANSI); used at discretion of employerused at discretion of employer

““Local limits” Local limits” – developed by organizations – developed by organizations if stressor is not addressed by regulation if stressor is not addressed by regulation or voluntary guidelines (i.e. manufacturer) or voluntary guidelines (i.e. manufacturer)

JOB CLASSIFICATIONS/JOB CLASSIFICATIONS/WORK HEALTH STATUSWORK HEALTH STATUS

Formal job descriptionsFormal job descriptions, and personnel , and personnel interviews with employees/supervisors. Directly interviews with employees/supervisors. Directly observe materials, operations, and activities!observe materials, operations, and activities!

Worker health status Worker health status – medical surveillance for – medical surveillance for health hazard recognition and workplace logs of health hazard recognition and workplace logs of incidents/injuries/illnesses for assistance with incidents/injuries/illnesses for assistance with stressor identification. stressor identification.

CONTROL MEASURESCONTROL MEASURES

DocumentDocument control measures used and control measures used and effectiveness by walk-through surveys. effectiveness by walk-through surveys.

MethodsMethods of eliminating or minimizing of eliminating or minimizing health hazard exposures. health hazard exposures.

ExamplesExamples: LEV, general ventilation; : LEV, general ventilation; isolation/enclosure; admin; PPE.isolation/enclosure; admin; PPE.

Observe also lack of control measures.Observe also lack of control measures.

PAST EVALUATIONS/PAST EVALUATIONS/IDENTIFY POTENTIAL HAZARDSIDENTIFY POTENTIAL HAZARDS

ReviewReview of past OH/IH or related evaluations. of past OH/IH or related evaluations. Determine:Determine: time elapsed; process, equipment, time elapsed; process, equipment, or workforce changes, identification of or workforce changes, identification of significant problems, and/or other indicators.significant problems, and/or other indicators.

Personnel interviews Personnel interviews and site review. Get and site review. Get workers involved workers involved for better acceptance. for better acceptance.

POTENTIAL HAZARD IDPOTENTIAL HAZARD ID

Apply Apply fundamentals fundamentals for hazard for hazard identification of job evaluations.identification of job evaluations.

Interview personnel Interview personnel for confirmation for confirmation related to: facilities, chemical, job tasks, related to: facilities, chemical, job tasks, work procedures, controls, and PPE.work procedures, controls, and PPE.

Get workers involved in survey for Get workers involved in survey for familiarizationfamiliarization to better accept findings to better accept findings and help implement recommendations. and help implement recommendations.

PRELIMINARY ASSESSMENT - PRELIMINARY ASSESSMENT - QUALITATIVE QUALITATIVE

FamiliarityFamiliarity with process/operation to with process/operation to qualitatively evaluate magnitude (e.g. qualitatively evaluate magnitude (e.g. chemical and physical hazards) without chemical and physical hazards) without benefit of instrumentation. benefit of instrumentation.

Visual observationsVisual observations; use of senses (i.e. ; use of senses (i.e. smell); inspection of control measures smell); inspection of control measures used and effectiveness; PPE. used and effectiveness; PPE.

WORKPLACE MONITORING -WORKPLACE MONITORING -QUANTITATIVE EVALUATIONQUANTITATIVE EVALUATION

Document exposure levelsDocument exposure levels either by either by measurement or use of semi-quantitative measurement or use of semi-quantitative methods. methods.

Strategy developed depends on the Strategy developed depends on the reason for evaluation. reason for evaluation.

Purpose is FIRST!Purpose is FIRST!

WORKPLACE MONITORING -WORKPLACE MONITORING -SAMPLING STRATEGYSAMPLING STRATEGY RecordkeepingRecordkeeping of work exposures of work exposures Documentation of health and safety regulatory Documentation of health and safety regulatory

compliancecompliance Identification of contaminant release sourcesIdentification of contaminant release sources Assistance in design and/or control evaluation Assistance in design and/or control evaluation Correlation of disease or injury with exposuresCorrelation of disease or injury with exposures

WORKPLACE MONITORING -WORKPLACE MONITORING -SAMPLING OBJECTIVESSAMPLING OBJECTIVES

Engineering testing, surveillance, or control; Engineering testing, surveillance, or control; designed to yield specific information designed to yield specific information

Compliance, health effects research, or Compliance, health effects research, or epidemiological purposes.epidemiological purposes.

Sampling produces data dependent on Sampling produces data dependent on purpose of the evaluation. purpose of the evaluation.

Purpose is #1Purpose is #1

STRESSOR IDENTIFICATIONSTRESSOR IDENTIFICATION

Hazard information Hazard information by familiarization and by familiarization and then prioritization (probability/consequence then prioritization (probability/consequence of overexposure) based on significance to of overexposure) based on significance to select stressors for monitoring. select stressors for monitoring.

StressorsStressors may include: may include: chemical, physical, chemical, physical, biological agents as well as ergonomic and biological agents as well as ergonomic and psychological elements.psychological elements.

CONTAMINANT ESTIMATIONCONTAMINANT ESTIMATION

Reasonable estimateReasonable estimate of contaminant of contaminant concentrations help with sampling strategy concentrations help with sampling strategy to outline assessment time intervals, to outline assessment time intervals, selection of equipment, methods, etc. selection of equipment, methods, etc.

Info from walk-through survey, personnel Info from walk-through survey, personnel discussions, degree of familiarity of similar discussions, degree of familiarity of similar operations, past data examination, etc. operations, past data examination, etc.

SAMPLING AND ANALYTICALSAMPLING AND ANALYTICALMETHOD SELECTIONMETHOD SELECTION

Use accurate and appropriate analytical methods Use accurate and appropriate analytical methods and calibrated sampling equipment. Knowledge and calibrated sampling equipment. Knowledge of interferences, detection limits, etc.of interferences, detection limits, etc.

PrinciplesPrinciples – validated methods (OSHA, NIOSH). – validated methods (OSHA, NIOSH). Communicate with lab!Communicate with lab!

Specificity, selectivity, reproducibilitySpecificity, selectivity, reproducibility, etc. for , etc. for methods and also direct-reading instruments.methods and also direct-reading instruments.

LimitationsLimitations - combine workplace observations - combine workplace observations with measurements for result interpretation. with measurements for result interpretation.

EQUIPMENT SELECTIONEQUIPMENT SELECTION

Type of analysis or information required Type of analysis or information required Efficiency of instrumentEfficiency of instrument Reliability of equipment under various field Reliability of equipment under various field

use conditionsuse conditions Portability and ease of instrument use Portability and ease of instrument use Personal choice of IH by past experiencePersonal choice of IH by past experience No single instrument exists – No single instrument exists –

universal/general vs. specific unit.universal/general vs. specific unit.

EQUIPMENT CALIBRATIONEQUIPMENT CALIBRATION

CalibrationCalibration – necessary to insure data – necessary to insure data representative of exposures; results based representative of exposures; results based on instrument accuracy (i.e. direct-reading) on instrument accuracy (i.e. direct-reading) and/or sampling and analytical methods; and/or sampling and analytical methods; pre- and post-calibration for air sample pre- and post-calibration for air sample volume; temperature/pressure adjustments.volume; temperature/pressure adjustments.

Direct-reading instruments Direct-reading instruments – known – known concentration of calibration gas for unit.concentration of calibration gas for unit.

Proper PPEProper PPE by IH during field work. by IH during field work.

SAMPLING STRATEGY SAMPLING STRATEGY

Overall plan or framework includes Overall plan or framework includes type and type and number of samplesnumber of samples to be collected; to be collected; the the methods usedmethods used, and accuracy, , and accuracy, and and monitoring objectivesmonitoring objectives. .

Confident decision and minimum cost/effort. Confident decision and minimum cost/effort. Complicated by numerous variablesComplicated by numerous variables (i.e. time, location, movements).(i.e. time, location, movements).Exposure profile statistically by lognormal Exposure profile statistically by lognormal distribution with a GSD between 2 to 5. distribution with a GSD between 2 to 5.

SAMPLING STRATEGYSAMPLING STRATEGY

WHAT and WHY? WHAT and WHY? By Objectives.By Objectives. WhereWhere to sample? to sample? WhenWhen to sample? to sample? How long How long to sample?to sample? WhomWhom to sample? to sample? How many How many samples to collect?samples to collect? HowHow should the samples be obtained? should the samples be obtained?

WHERE???WHERE???

Personal or general areaPersonal or general area at operation at operation

or in work spaceor in work space Breathing zoneBreathing zone for personals for personals Location(s) are dictated by Location(s) are dictated by NeedNeed Source of contaminants by Source of contaminants by AreaArea

or to evaluate engineering controls.or to evaluate engineering controls.

WHEN???WHEN???

Determined by Determined by informationinformation required required Type of operation assessedType of operation assessed Multiple shiftsMultiple shifts Geographic/climatologic conditions Geographic/climatologic conditions

HOW LONG???HOW LONG???

Minimum time Minimum time determined by time interval determined by time interval needed to obtain sufficient amount of needed to obtain sufficient amount of contaminant on media for lab analysis. contaminant on media for lab analysis.

SensitivitySensitivity of analytical procedure of analytical procedure Dependent on Dependent on contaminant concentrationcontaminant concentration Full work shift Full work shift for compliancefor compliance Work tasks; partial periods; multiple Work tasks; partial periods; multiple

samples to measure entire work shiftsamples to measure entire work shift

WHOM???WHOM???

Depends on Depends on purposepurpose of monitoring. of monitoring. For compliance, then sample For compliance, then sample maximum risk maximum risk

employees with highest exposuresemployees with highest exposures. . Random sample by exposure group for a Random sample by exposure group for a

comprehensive assessmentcomprehensive assessment

HOW MANY???HOW MANY???

Dependent on the purpose and Dependent on the purpose and No Set Rule! No Set Rule!

For For comprehensive assessmentcomprehensive assessment, minimum , minimum of six samples for each exposure group may of six samples for each exposure group may be needed for acceptability. be needed for acceptability.

With constraints, use of semi-quantitative With constraints, use of semi-quantitative methods. Employ personal experience to methods. Employ personal experience to collect optimal sample number for situation. collect optimal sample number for situation.

HOW???HOW???

Instrument choice Instrument choice depends on:depends on:-- Portability and ease of usePortability and ease of use-- Efficiency and analytical methodEfficiency and analytical method-- Reliability for conditions of field useReliability for conditions of field use-- Type of analysis or info required Type of analysis or info required

Choice of instrumentation and results Choice of instrumentation and results dependent on capabilities of the laboratory.dependent on capabilities of the laboratory.

SAMPLE COLLECTIONSAMPLE COLLECTION

Follow strategy to not bias results or Follow strategy to not bias results or compromise the integrity of conclusions. compromise the integrity of conclusions.

Adjust or modify as needed but record! Adjust or modify as needed but record! Phased sampling strategy is optionPhased sampling strategy is option Review procedures; equipment/supplies Review procedures; equipment/supplies Understand impact on the work Understand impact on the work

environment; worker participation environment; worker participation Recordkeeping – extensive notes and Recordkeeping – extensive notes and INFO

to assist with data interpretationto assist with data interpretation Handling – labeling; chain of custodyHandling – labeling; chain of custody

SAMPLING AND ANALYTICAL SAMPLING AND ANALYTICAL PROCEDURESPROCEDURES

Selection of measurement method depends Selection of measurement method depends on strategy requirements and purpose with: on strategy requirements and purpose with: duration of sampling duration of sampling [TWA vs. STEL], [TWA vs. STEL], sensitivity of the method/detection limit, sensitivity of the method/detection limit, freedom from interferences/result bias, freedom from interferences/result bias, time for reporting of results, time for reporting of results, intrusiveness, and intrusiveness, and accuracy.accuracy.

DURATION OF SAMPLINGDURATION OF SAMPLING

Dependent on Dependent on averaging time of OELs: averaging time of OELs: 8-hour TWAs 8-hour TWAs – single vs. several – single vs. several

consecutive samples over 8 hours consecutive samples over 8 hours Short-term or instantaneous (i.e. grab) – Short-term or instantaneous (i.e. grab) –

not for full-shift exposures not for full-shift exposures STELsSTELs – 15 minutes – 15 minutes CeilingCeiling – minutes. – minutes.

OTHER SAMPLING AND OTHER SAMPLING AND ANALYTICAL PARAMETERSANALYTICAL PARAMETERS

CConsideronsider sensitivity of method/detection limit.sensitivity of method/detection limit. Method detection less than OEL of interest.Method detection less than OEL of interest.

Aware that other airborne substances may cause Aware that other airborne substances may cause interferencesinterferences..

Laboratory can provide guidance. Laboratory can provide guidance.

Turnaround – routine vs. rush. Turnaround – routine vs. rush.

Intrusiveness/Intrusiveness/RepresentativeRepresentative considerations. considerations.

Accuracy – environmental variability.Accuracy – environmental variability.

INTERPRETATION OF INTERPRETATION OF SAMPLING RESULTSSAMPLING RESULTS ConcentrationsConcentrations CalculationsCalculations based on time periods/use of based on time periods/use of

assumptions and professional judgment/OELs.assumptions and professional judgment/OELs. Test statisticsTest statistics Professional judgment Professional judgment – acute/chronic– acute/chronic Information for Information for data interpretationdata interpretation

-- Precise nature of material/agentPrecise nature of material/agent

-- Intensity/magnitude of exposureIntensity/magnitude of exposure

-- Reliable knowledge of frequency/duration. Reliable knowledge of frequency/duration.

COMPARISONSCOMPARISONS

TWAs vs. STELSTWAs vs. STELS Best sampling strategy for full-shift integrated Best sampling strategy for full-shift integrated

personal sampling; short-term tasks about personal sampling; short-term tasks about variability [peak/ceiling - instantaneous]; variability [peak/ceiling - instantaneous]; general area samples not specifically general area samples not specifically recommended.recommended.

OELsOELs – direct result comparison with: – direct result comparison with: OSHA PELs, OSHA PELs, ACGIH TLVs, ACGIH TLVs, NIOSH RELs, NIOSH RELs, AIHA WEELs, etc.AIHA WEELs, etc.