Aerosol Sampling

Preface xvii A SCIENTIFIC FRAMEWORK FOR AEROSOL SAMPLING 1 1 Introduction 3 1.1 Aerosols 3 1.2 Particle size 4 1.3 Elementary particle size statistics 5 1.4 Aerosol measurement 8 1.5 Sampler performance characteristics 9 References 12 2 Fluid and aerosol mechanical background 13 2.1 Fluid mechanical background 13 2.2 Aerosol mechanics 22 References 33 3 Experimental methods in aerosol sampler studies 35 3.1 Introduction 35 3.2 Methodology for assessing sampler performance 35 3.3 Scaling relationships for aerosol samplers 38 3.4 Test facilities 39 3.5 Test aerosol generation 50 3.6 Reference methods 60 3.7 Assessment of collected aerosol 60 3.8 Aerosol sampler test protocols and procedures 61 References 68 4 The nature of air flow near aerosol samplers 71 4.1 Introduction 71 4.2 Line and point sink samplers 71 4.3 Thin-walled slot and tube entries 73 4.4 Thick-walled tubes 75 4.5 Simple blunt samplers facing the wind 76 4.6 Blunt samplers with orientations other than facing the wind 82 4.7 More complex sampling systems 89 4.8 Effects of freestream turbulence 90 References 90 5 Aerosol aspiration in moving air 93 5.1 Introduction 93 5.2 Thin-walled tube samplers 94 5.3 Blunt samplers 116 References 127 6 Aspiration in calm and slowly moving air 131 6.1 Introduction 131 6.2 Sampling in perfectly calm air 131 6.3 Slowly moving air 149 References 155 7 Interferences to aerosol sampling 157 7.1 Introduction 157 7.2 Interferences during aspiration 157 7.3 Interferences after aspiration 173 References 188 8 Options for aerosol particle size selection after aspiration 193 8.1 Introduction 193 8.2 Elutriation 194 8.3 Filtration by porous foam media 197 8.4 Centrifugation 201 8.5 Impaction 205 8.6 Diffusion 211 8.7 Other particle size-selective mechanisms 213 References 215 B STANDARDS FOR AEROSOLS 219 9 Framework for aerosol sampling in working, living and ambient environments 221 9.1 Introduction 221 9.2 Exposure to aerosols 222 9.3 Framework for health-related aerosol sampling 227 9.4 Non-health-related aerosol standards 233 References 235 10 Particle size-selective criteria for coarse aerosol fractions 237 10.1 Introduction 237 10.2 Experimental studies of inhalability 237 10.3 Particle size-selective criteria for the inhalable fraction 247 10.4 Overview 252 References 253 11 Particle size-selective criteria for fine aerosol fractions 255 11.1 Introduction 255 11.2 Studies of regional deposition of inhaled aerosols 255 11.3 Criteria for fine aerosol fractions 268 11.4 Overview 282 References 285 12 Health effects and Limit values 289 12.1 Introduction 289 12.2 Aerosol-related health effects 289 12.3 The processes of standards setting 292 12.4 Occupational exposure limits (OELs) 292 12.5 Ambient atmospheric aerosol limits 297 12.6 Special cases 301 References 305 C AEROSOL SAMPLING INSTRUMENTATION 309 13 Historical milestones in practical aerosol sampling 311 13.1 Introduction 311 13.2 Occupational aerosol sampling 312 13.3 Ambient atmospheric aerosol sampling 319 References 323 14 Sampling for coarse aerosols in workplaces 327 14.1 Introduction 327 14.2 Static (or area) samplers for coarse aerosol fractions 327 14.3 Personal samplers for coarse aerosol fractions 333 14.4 Analysis of performance data for inhalable aerosol samplers 352 14.5 Passive aerosol samplers 354 References 356 15 Sampling for fine aerosol fractions in workplaces 359 15.1 Introduction 359 15.2 Samplers for the respirable fraction 359 15.3 Samplers for the thoracic fraction 385 15.4 Samplers for PM2.5 391 15.5 Thoracic particle size selection for fibrous aerosols 393 15.6 Sampling for very fine aerosols 394 15.7 Simultaneous sampling for more than one aerosol fraction 395 References 398 16 Sampling in stacks and ducts 403 16.1 Introduction 403 16.2 Basic considerations 403 16.3 Stack sampling methods 404 16.4 Sampling probes for stack sampling 410 16.5 Sampling for determining particle size distribution in stacks 414 16.6 Direct-reading stack-monitoring instruments 415 References 415 17 Sampling for aerosols in the ambient atmosphere 417 17.1 Introduction 417 17.2 Sampling for coarse ‘nuisance’ aerosols 417 17.3 Sampling for ‘black smoke’ 423 17.4 Sampling for total suspended particulate in the ambient atmosphere 425 17.5 Sampling for fine aerosol fractions in the ambient atmosphere 432 17.6 Meteorological sampling 440 References 442 18 Sampling for the determination of particle size distribution 447 18.1 Introduction 447 18.2 Rationale 447 18.3 Aerosol spectrometers 448 18.4 Cascade impactors 452 18.5 Other spectrometers 465 18.6 Particle size distribution analysis by microscopy 469 References 470 19 Sampling for bioaerosols 473 19.1 Introduction 473 19.2 Standards for bioaerosols 474 19.3 Technical issues for bioaerosol sampling 474 19.4 Early bioaerosol sampling 476 19.5 Criteria for bioaerosol sampling 477 19.6 Inertial samplers 477 19.7 Centrifugal samplers 485 19.8 ‘Total’ and inhalable bioaerosol 486 19.9 Other samplers 486 References 486 20 Direct-reading aerosol sampling instruments 489 20.1 Introduction 489 20.2 Optical aerosol-measuring instruments 490 20.3 Electrical particle measurement 503 20.4 Condensation nuclei/particle counters 504 20.5 Mechanical aerosol mass measurement 505 20.6 Nuclear mass detectors 509 20.7 Surface area monitoring 510 20.8 Analytical chemical methods 511 20.9 Bioaerosol monitoring 511 References 513 D AEROSOL SAMPLE APPLICATIONS AND FIELD STUDIES 517 21 Pumps and paraphernalia 519 21.1 Introduction 519 21.2 Air moving systems 519 21.3 Flow rate 524 21.4 Collection media 526 21.5 Analysis of collected samples 533 References 535 22 Field experience with aerosol samplers in workplaces 537 22.1 Introduction 537 22.2 Personal and static (or area) sampling 538 22.3 Relationship between ‘total’ and inhalable aerosol 539 22.4 Converting particle counts to particle mass 549 22.5 Field experience with samplers for respirable aerosol 558 22.6 Classification of workplace aerosols 562 22.7 Diesel particulate matter 568 22.8 The future of workplace aerosol measurement 569 References 570 23 Field experience with aerosol samplers in the ambient atmosphere 575 23.1 Introduction 575 23.2 ‘Nuisance’ dust 576 23.3 Total suspended particulate and black smoke 577 23.4 Black smoke and particle size fractions (PM10 and PM2.5) 580 23.5 Transition to particle size-selective sampling 582 23.6 PM10 585 23.7 PM2.5 589 23.8 Personal exposures to PM10 and PM2.5 589 23.9 Classification of ambient atmospheric aerosols 593 References 596 Index 599