Measurement techniques, advances and limitations

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1 Measurement techniques, advances and limitations Joakim Pagels and Aneta Wierzbicka Ergonomics and Aerosol Technology Lund University Workplace and Indoor Aerosols Conference 2012 Lund University

Perron, G. Frank, S. Sjögren, B. Svenningsson, E. Swietlicki Nuclear Physics, Lund University M. Messing, K.

2 Aerosol Group C. Isaxon, E. Nordin, P. Nilsson, C. Svensson, L. Ludvigsson, A. Wierzbicka, J. Löndahl, J. Rissler, J. Pagels, A. Gudmundsson, M. Sanati, M. Bohgard, Ergonomics & Aerosol Technology, Lund University A. Eriksson, C. Wittbom, M. Sporre, E. Fors, M. Frosch Mogensbæk Foverskov, N. Perron, G. Frank, S. Sjögren, B. Svenningsson, E. Swietlicki Nuclear Physics, Lund University M. Messing, K. Deppert Solid State Physics, Lund Universit M. Hedmer, H. Tinnerberg Occupational and Environmental Medicine, Lund University Workplace and Indoor Aerosols Conference 2012 Lund University

3 Workplace and Indoor Aerosols Conference 2012 Lund University

4 Outline Which particle properties should be measured? Different types of measurements depending on purpose of measurements Small portable instruments Detail characteristics with in situ techniques Workplace and Indoor Aerosols Conference 2012 Lund University

5 Which particle properties should be measured mass concentration number concentration particle size surface area geometric form chemical composition bioavailable transition metals solubility acidity particle surface chemistry core chemistry Workplace and Indoor Aerosols Conference 2012 Lund University

6 Measurements Personal exposure Monitoring in microenvironments Detail characterisation for specific purpose Workplace and Indoor Aerosols Conference 2012 Lund University

7 Personal exposure Collection of particles on filters for: Gravimetric analysis Chemical speciation (ion chromatography, OC/EC analysis, PIXE, X-ray fluorescense) Morphology assessment (TEM, SEM) Workplace and Indoor Aerosols Conference 2012 Lund University

8 Monitoring in microenvironments Workplace and Indoor Aerosols Conference 2012 Lund University

9 Workplace and Indoor Aerosols Conference 2012 Lund University

10 Workplace and Indoor Aerosols Conference 2012 Lund University

Number concentration - Hand-held Condensation

Conc. limit 100 000 cm -3-500 000 cm -3 - Battery

every 6-8 hours - Has to be kept in horisontal

11 Number concentration - Hand-held Condensation Particle Counter (CPC) nm to about 1 m - Conc. limit cm cm -3 - Battery operation about 5-6 hours - Requires liquid refill every 6-8 hours - Has to be kept in horisontal orientation Workplace and Indoor Aerosols Conference 2012 Lund University

12 Approximation of mass concentration - Photometers - Robust, cheap instruments - Fast response to detect sudden changes (1s) - But.. cannot be used as an absolute mass concentration measuring instrument - Based on light scattering dependant on refractive index (material) and size distribution - Overestimate the mass concentrations - ~ 0.1 to 10 m Workplace and Indoor Aerosols Conference 2012 Lund University

13 Photometer with simultaneous collection of the particles on the filter Schematics DUSTTRAK II courtesy of Thomas Krinke, TSI Workplace and Indoor Aerosols Conference 2012 Lund University

14 microaethalometer - Black Carbon measurement - Pocket sized - Battery operated - Measures the change in absorption of transmitted light due to continuous collection of aerosol deposit on filter. - Precision ±0.1 μg BC/m3, Workplace and Indoor Aerosols Conference 2012 Lund University

Number concentration and particle size small handheld

Aerasense NanoCheck/ NanoDiff, Grimm Small, portable,

personal exposure assessment Open up new possibilities

15 Number concentration and particle size small handheld instruments DISCMini, Matter Aerosol Nanotracer, Aerasense NanoCheck/ NanoDiff, Grimm Small, portable, handheld, battery operated Easy to use Suitable for personal exposure assessment Open up new possibilities Workplace and Indoor Aerosols Conference 2012 Lund University

Small handheld instruments principle of operation - Unipolar diffusion charging of the particles - Measurement of the particle induced current Unipolar charging

16 Small handheld instruments principle of operation - Unipolar diffusion charging of the particles - Measurement of the particle induced current Unipolar charging Schematics courtesy of Martin Fierz Two stages with different size dependant deposition efficiency Workplace and Indoor Aerosols Conference 2012 Lund University

17 Small handheld instruments principle of operation Components of the diffusion size classifier Fierz et al., 2007, Field measurement of particle size and number concentration with the Diffusion Size Classifier (DiSC), SEA interantional Workplace and Indoor Aerosols Conference 2012 Lund University

18 Testing presale instruments Dahl et al., 2009 Number concentration and particle diameter of candle smoke Number concentration of mobile on the road measurements

19 Example of measurements in homes PINDA project Isaxon et al, Two persons having a party; playing music, smoking several cigarettes Cooking food Working by the computer, using the printer All windows in the appartment open Workplace and Indoor Aerosols Conference 2012 Lund University

20 Photos courtesy of Maria Hedmer, OEM, Lund University Workplace and Indoor Aerosols Conference 2012 Lund University

21 Asbach et al., 2012 Comparability of portable nanoparticle exposure monitors. Annals of Occupational Hygiene, in press Compared instruments - 6 handheld CPCs (model 3007, TSI) - 2 DISCmini (Matter Aerosol) - 3 Nanotracer (Aerasense) - 2 NanoCheck (model 1.320, Grimm Aerosoltechnik) - Aerotrak 9000 (TSI) - Fast Mobility Particle Sizer (FMPS, TSI model 3091) Aerosols used for intercomparison - Sodium chloride (NaCl) - Di-Ethyl-Hexyl-Sebacate (DEHS, C 26 H 50 O 4) - soot particles Workplace and Indoor Aerosols Conference 2012 Lund University

22 Asbach et al., 2012 Comparability of portable nanoparticle exposure monitors. Annals of Occupational Hygiene, in press CPCs DISCmini Nanotracer Nanocheck Size range (nm) Pre classifier Manufacturer specified accuracy Number concentration accuracy in the intercomparison study Deviations Sizing accuracy specified by manufacturer particles above 700 nm are removed ± 20% ± 30% ± /cm 3 ± 5% ± 20% ± 30% ± 30% ± 30% overestimation of number conc in case of DEHS between 250 and 594% ± 30% ± 10 nm ± 5% underestimation of soot particles 58% Sizing accuracy in the intercomparison study Lung deposited surface area ± 30% ± 30% in good agreement with FMPS within ± 30% in good agreement with FMPS for NaCl and DEHS within ± 6%, deviation for soot sizing

Tiered approach for exposure assessment presented by German Chemical IndustryAssociation yes no no 1 1 no ENM from activity; chemical identity of ENM known; their origin is elsewhere Are risk

Tier 3 Expanded Measurement (e.g. with SMPS, CPC, chem. analysis, etc.) yes?

23 Tiered approach for exposure assessment presented by German Chemical IndustryAssociation yes no no 1 1 no ENM from activity; chemical identity of ENM known; their origin is elsewhere Are risk management measures efficient? Tier 1 Data Gathering no? Tier 2 Screening (e.g. with CPC) yes? Tier 3 Expanded Measurement (e.g. with SMPS, CPC, chem. analysis, etc.) yes?? Can the release of nanoscale particles into the workplace air be reasonably excluded during production, handling or prcessing? Significant increase of concentration over background? Clear evidence ofchemcial identity of the ENM? Take additional risk management measures to mitigate exposure yes no Slide: Courtesty of Christof Asbach Tier 2: Screening of only total concentrations, e.g. with (handheld) CPC, diffusion chargers, etc. Tier 3: Expanded analysis of workplace aerosol: Chemical analysis Size distribution (micron und submicron) Number, surface area, and mass concentration Determination of particle background Documentand archive Based on: VCI position paper Tiered approach to an exposure measurement (2011); Tiered Approach.pdf Check after 2 years or in case of changes Workplace and Indoor Aerosols Conference 2012 Lund University

24 What can be measured on-line? Particle Size Mass, Number, Surface Area Concentration Size-Resolved Composition Volatility Hygroscopic Growth / Water Solubility Agglomerate structure

25 Measurement Technique Posters Aerosols 2012 Järvinen A. et al. Nilsson P.T. et al. Asbach C. et al. Fierz, M. et al Gnewuch H. et al. Neubauer N. et al. Huotari J. et al. Krinke T. et al. Steer B. et al. Calibration of diffusion charger based electrical aerosol sensors Laser Vaporizer Aerosol Mass Spectrometry to detect metal NPs Portable monitor for the assessment of exposure to nanoparticles Nanoparticle Dosimeter for Easy Workplace Exposure Monitoring Scanning-Flow Diffusion-based Particle Size Spectrometer (SFDiPS) Specific detection of palladium nanoparticles Impedance Spectroscopy of Particles from a Steel Plant Development of a Portable, Battery-Operated Nanoparticle Sizer Comparison Studies of a Portable SMPS System Portable instruments: downscaling in size and cost On-line instruments to selectively detect metals etc

26 Background Unaltered particles sized by major transport and deposition mechanisms Time Resolved, Size Resolved Avoid particle gas-phase interactions Evaporation, Adsorption of gas phase, Degradation Avoid changes in morphology

min ~ s ~ s ~ s Size Resolution High Medium High Medium Sensitivity High

27 Size Distributions In Situ Techniques SMPS/FMPS APS SMPS FMPS / DMS APS ELPI Size range (nm) Time Resolution ~ min ~ s ~ s ~ s Size Resolution High Medium High Medium Sensitivity High Medium High Medium Eq. diameter Mobility Mobility Aerodynamic Aerodynamic

28 Emissions in Production of Multi-walled CNTs Aerodynamic Particle Sizer Hedmer et al. Senn 2012

29 Multi-walled CNTs SEM analysis Poster: Ludvigsson et al.

30 Highly Time Resolved Mobility Analysis Welding Fumes Quickly changing concentrations Need high time resolution

2009 Alveolar Surface Area Concentration [nm²/cm³] 7x10 9

31 Surface Area Measurements SA dep (dp)~dp 2 *DF(dp) Fissan et al. 2007, Asbach et al Alveolar Surface Area Concentration [nm²/cm³] 7x10 9 6x10 9 5x10 9 4x10 9 3x10 9 2x10 9 1x :01:02 13:08:36 13:16:00 13:23:24 13:32:16 Time NSAM FMPS

32 Aerosol Mass Spectrometry ddd Jayne et al DeCarlo et al. 2007

33 Time-Resolved PAH Analysis in Transient Wood Combustion Add fuel Flaming Phase Burnout Phase Erikson et al. AAAR 2012

34 Laser Vaporiser Aerosol Mass Spectrometer Nd:YAG laser λ=1064 nm Onasch et al. AS&T 2012

35 Selective Emissions of Metal NPs Opened up the spark discharge generator Nilsson et al., SENN 2012

In-Situ Measurements of Agglomerates Aerosol Particle Mass Analyzer (APM)) Rotating outer electrode Rotating inner electrode Air gap r 2 V APM r 1 F c qe Aerosol in F el Particles

36 In-Situ Measurements of Agglomerates Aerosol Particle Mass Analyzer (APM)) Rotating outer electrode Rotating inner electrode Air gap r 2 V APM r 1 F c qe Aerosol in F el Particles are pass APM if: m qe qe 2 r 2 mr r qv 2 ln 2 APM r 2 / r 1 Axis of rotation Aerosol out Ehara et al McMurry et al 2002 Presentation at the IAC Jenny Rissler

37 In-Situ Measurements of Agglomerates - Aerosol Particle Mass Analyzer (APM)) Rotating outer electrode Rotating inner electrode Air gap r 2 V APM r 1 F c qe Aerosol in Particles are pass APM if: APM Aerosol in DMA Axis of rotation CPC m eff d 6 3 me Aerosol out Ehara et al McMurry et al 2002 Presentation at the IAC Jenny Rissler

38 Particle Types at a Busy Street eff =0.4 g/cm3 eff =1.5 g/cm3 m eff d 6 3 me Rissler et al EAC 2012

Surface Area of Metal NPs Aggregates and sintered

sintered particle Surface Area decreases a factor

39 Surface Area of Metal NPs Aggregates and sintered particles of the same mass (TDMA-APM) Aggregates with primary particle size of 5 nm Mobility diameter is 60 nm for aggregates and 31 nm for the sintered particle Surface Area decreases a factor of ~ 5 upon sintering (Messing et al. 2012, Nanotoxicology)

Tandem-DMA set-up Mixing status Tandem DMA With a TDMA the properties of single particles can be studied Combustion Aerosol Candle Aerosol from Chamber Ambient Aerosol CPC

40 Tandem-DMA set-up Mixing status Tandem DMA With a TDMA the properties of single particles can be studied Combustion Aerosol Candle Aerosol from Chamber Ambient Aerosol CPC Monodisperse Aerosol CPC Bipolar Charger Drier DMA1 DMA2 Humidifier Humidifier or Thermo-desorber, Heater Chemical Reactor etc. Figure 3. Schematic figure of the TDMA Technique

41 Particle Types from Indoor Sources

42 Summary In-Situ Techniques Size distributions can be measured with high accuracy and time resolution. Downscaling in dimensions and price on-going Volatile coatings (Organics etc) can be removed in thermodenuder to sample d particles only. Lung deposited surface area determined using NSAM, needs to be confirmed for agglomerates. The morphology of coated or core particle can be determined using DMA-APM and UNPA techniques Particle hygroscopicity/water solubility estimated using T-DMA techniques. Highly time- and size resolved composition can be measured using Aerosol MS techniques. Still expensive and bulky. Separation into particle types (external mixture) according to volatility, hygroscopicity and morphology using tandem techniques

Introduction and Initial Field Data of a Novel, Portable Nanoparticle Sizing Instrument

Introduction and Initial Field Data of a Novel, Portable Nanoparticle Sizing Instrument Torsten Tritscher 1, Thomas J. Krinke 1, Axel F. Zerrath 2, Erik Willis 2 and Oliver F. Bischof 1 1 TSI GmbH, Particle