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Kathlyn Boone
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com Featured Speaker Achim Edfelder North American

1 Detect, Measure, Analyze. Thank You for Attending Today s Webinar: Aerosol Monitoring 201 Your Host Jim Behnke Outside Sales RAECO-LIC LLC jim@raeco.com Featured Speaker Achim Edfelder North American Sales Manager GRIMM Technologies achim.edfelder@grimm.durag.com Follow the Conversation #RAECOWebinar

2 Aerosol Monitoring 201 Why using a spectrometer instead of a photometer? Webinar Aerosol Monitoring 201 1

3 Agenda Spectrometer vs photometer Optics design Measurement values provided Strengths & limitations Implications to the data Impact of humidity on measurement precision Techniques to minimize impact of humidity Impact of refractive index of target material to each Handling the Mie scattering Indoor & outdoor monitoring Safety & health FEM - Governmental measurement networks Industry R & D Calibration of instruments Questions and answers Webinar Aerosol Monitoring 201 2

4 Spectrometer VS Photometer What is a spectrometer? A spectrometer measures every single particle crossing a sharp defined optical volume. The spectrometer detects the number of scattering light signals (impulses) and intensity of each particle. The basic information from a spectrometer is thus how many particles of which size (impulse intensity equals particle size) are present in the air. Fact: Every single particle is Measured Counted Classified From this particle size distribution further mass fractions can be calculated. Webinar Aerosol Monitoring 201 3

5 Spectrometer VS Photometer What is a photometer? A photometer measures a group of particles being present in a larger optical sensing volume. The photometer detects the reflection/ brightness/ scattering of the light source from the group of particles. The basic information from a photometer is thus a light intensity caused by a group of particles of an unknown particle size distribution present in the air. Fact: Many particles are illuminated by a light source. This group of particles creates a scattering signal. A certain scattering signal intensity correlated to one PM value only. Other mass fractions have to be estimated. No information on the particle size composition possible no secure measurement of actual airborne particles Webinar Aerosol Monitoring 201 4

6 Spectrometer VS Photometer Spectrometer principle Photometer principle Precise examination of what is in the air Approximate estimation of what is in the air Webinar Aerosol Monitoring 201 5

7 Optics Design Rinsing air Aerosol inlet Laser diode Aerosol focusing Defined optical volume Collimator Photo diode Wide field reflector Light trap PTFE filter Webinar Aerosol Monitoring 201 6

8 Optics Design A laser creates a round beam. By dint of the collimator a sharp defined, laser-bench adjusted optical volume of 1.6x1.6mm and 40 µm height is established. Particles entering the measurement cell at 1.25 m/s are accelerated just right before the optical volume to 19 m/s. This will drag the particles apart from each other to realize a single particle detection up to 3 million particles per liter. The particle being inside the optical volume, its scattering light is captured at 90 by the photo diode at a narrow opening angle from The wide field reflector offering an opening angle of reflects the scattering light back to the photo diode. Webinar Aerosol Monitoring 201 7

9 Optics Design After classifying the particle into the scattering light intensity correlating size bin, it is deposited on the device-integrated PTFE filter. This filter has two functions: 1. Since every particle sucked in by the device is deposited on the PTFE filter, a precise mass correlation can be established. Further chemical, microscopic and gravimetric analysis thus possible. 2. Filtering out all particles from the sample air provides clean air. This air is refed into the optical chamber to continuously rinse the optics without interfering with the particles inside the optical volume. Constantly clean cell realized. Webinar Aerosol Monitoring 201 8

10 Measurement values provided Spectrometer Since the basic information of the spectrometer measurement is particle size and counts per volume (for GRIMM = particles per liter), any desired mass value can be calculated. An empiric density suitable for standard indoor air is part of the algorithm. With the PTFE filter feature correlations can easily be established and mass values accordingly corrected, whenever you are facing specific particle sources to be measured. Photometer Many photometers need an impactor, sizeselective head, or precipitator to cut out a certain size range to enable the device measuring the remaining size fraction more or less correctly. Thus, often only one mass fraction value PM value is measured by the photometer. Photometers providing more than one PM value are still calibrated to ONE certain PM value only. The other PM values are based on an estimation of what is expected to be inside the group of particles. Webinar Aerosol Monitoring 201 9

Measurement values provided Spectrometer Particle size distribution Total counts Particle mass distribution Total

5 PM1 Inhalable Thoracic Respirable = PM4 Particle surface offered All mass values are given in µg/m³ as precise as

5 PM1 PMtotal The list under Aerosol inlet is an example of the most possible PM values.

11 Measurement values provided Spectrometer Particle size distribution Total counts Particle mass distribution Total suspended particles (TSP) PM10 PM4 = Respirable PM2.5 PM1 Inhalable Thoracic Respirable = PM4 Particle surface offered All mass values are given in µg/m³ as precise as two digits after the decimal point. Photometer Size selective head One PM value Total aerosol inlet PM10 PM4 PM2.5 PM1 PMtotal The list under Aerosol inlet is an example of the most possible PM values. The instrument is calibrated to one PM value only, e.g. PM2.5 All values are given in mg/m³ with 3 digits after the decimal point. Thus the smallest possible number and precision is 1 microgram Webinar Aerosol Monitoring

12 Strengths & Limitations Measurement values Dust concentration Spectrometer Photometer Strengths Limitation Strengths Limitation Wide variety of different values (counts, mass, surface) Single particle measurement up to 3 million P/L Coincidence beyond Particle group measurement One or few mass values only No precise particle number measurement Humidity effects Single effects Exponential effects Particle post-analysis Measurement precision Research capability Digital as well as EVERY sucked in particle on a filter 1 particle per liter 0.01 µg/m³ 3% tolerance Precise particle analysis Continuous monitoring Possible Possible No digital post-analysis. Not all or no particles sucked in on a filter No particle conc. 1 µg/m³ Only PM Webinar Aerosol Monitoring

13 Implications to the data Certain ambient conditions and/ or aerosol sources can have an implication to the measurement data. Such conditions/ sources can be: High humidity Particle shape Particle color Webinar Aerosol Monitoring

14 Impact of humidity on measurement precision Scattering light changes with the influence of humidity. Minor change for single particle scattering. Major change for scattering light caused by a number of particles effect rises exponential. Webinar Aerosol Monitoring

$particle number per size bin, humidity effects will appear within the size bins and not within mass fractions of particles Particle$ growth happens PER size bin conversion to mass PER size bin possible error PER size bin +H 2 O +H 2 O +H 2 O If particle grow by

growth happens PER size bin conversion to mass PER size bin possible error PER size bin +H 2 O +H 2 O +H 2 O If particle grow by

15 Implications to the data Humidity changes the optical characteristics of the particles As the spectrometer s basic information is particle number per size bin, humidity effects will appear within the size bins and not within mass fractions of particles Particle growth happens PER size bin conversion to mass PER size bin possible error PER size bin +H 2 O +H 2 O +H 2 O If particle grow by humidity within the boundaries of one size bin, no misinterpretation/ error takes place! Webinar Aerosol Monitoring

16 Implications to the data A nephelometer / photometer collects the scattering light from a group of particles. A discrimination between particles affected by humidity and not affected is not possible. Nephelometers are calibrated against one mass fraction value (often PM2.5). The humidity effects will affect a complete mass fraction and cannot be taken out of consideration for no information upon particle size distribution is available. Particle growth happens PER particle Group signal measurement affects mass fraction Single particles affected falsify complete PM fraction Error guaranteed! +H 2 O PM1 PM2.5 PM4 PM10 Webinar Aerosol Monitoring

17 Implications to the data Particle sizes affected Effect on smaller sizes Minor change is number is major change in mass Biggest effect on PM4, PM2.5, PM1 Mass reading instruments (nephelometers) are subject to misreading in fog/ haze/ high humidity Direct reading instruments (Spectrometers) can buffer humidity effects and let the user take out certain values upon demand. Source: Tripathi et al: Measurements of atmospheric parameters during Indian Space Research Organization Geosphere Biosphere Programme Land Campaign II at a typical location in the Ganga basin: 1. Physical and optical properties Webinar Aerosol Monitoring

Impact of humidity on measurement precision Result: Particles appear bigger than they actually are because

Consequences: Spectrometer: Particle growth buffering possible Particle sizes can be taken out from

value completely affected Scattering signal from affected particles cannot be excluded from the particle

18 Impact of humidity on measurement precision Result: Particles appear bigger than they actually are because of a hydration shell around the particle itself. Consequences: Spectrometer: Particle growth buffering possible Particle sizes can be taken out from consideration Particle mass effect based on single size bin Nephelometer: No particle classification PM value completely affected Scattering signal from affected particles cannot be excluded from the particle group Particle mass being subject to the power of the third when calculating mass (diameter volume) makes the mass values tremendously higher. Webinar Aerosol Monitoring

19 Techniques to minimize impact of humidity By heat Isotherm by removing water molecules Webinar Aerosol Monitoring

Techniques to minimize impact of humidity Heat: The sample air is being dried by applying heat to the

Isotherm: Humidity is being extracted by applying low pressure outside a Nafion membrane through

This makes the water molecules permeate through the wall, away from the particles and thus the

20 Techniques to minimize impact of humidity Heat: The sample air is being dried by applying heat to the sample pipe. This raises the dew point and thus formation of a hydration shell is avoided. Isotherm: Humidity is being extracted by applying low pressure outside a Nafion membrane through which the humid air is guided. This makes the water molecules permeate through the wall, away from the particles and thus the formation of a hydration shell is avoided. Reducing humidity Heat No heat Advantage Disadvantage Advantage Disadvantage Cheap Losing SVC No loss of SVC Complex Webinar Aerosol Monitoring

$Impact of refractive index of target material The refractive index is an important part of the scattering intensity.$

21 Impact of refractive index of target material The refractive index is an important part of the scattering intensity. It describes the color of the particle divided into the real part (scattering) and the imaginary part (absorption). Webinar Aerosol Monitoring

22 Impact of refractive index of target material Scattered intensity I is a function of α = size parameter = π dp/λ where dp = particle diameter, λ = incident wavelength (655 nm) BACKWARD SCATTERED m = refractive index = n i where n = real part (scattering), i = imaginary part (absorption) Θ = scattering angle where ~0 = backward scattered, ~180 = forward scattered [Baron & Willeke, 2001, Haller 1999] Webinar Aerosol Monitoring

23 Impact of refractive index of target material [Baron & Willeke, 2001, Haller 1999] Webinar Aerosol Monitoring

24 Impact of refractive index of target material Researchers found out: The scattering intensity captured inside the GRIMM measurement cell is not influenced By the imaginary part (the color) of the particle. Increasing the imaginary part (measuring darker particles) Scattering intensity does not change. Colors of one group stay in one line They overlap, i.e. color has no influence [Baron & Willeke, 2001, Haller 1999] Webinar Aerosol Monitoring

25 Handling the Mie scattering Mie is valid for particle sizes in the size range same as the incident wavelength (depending on the light source!) MIE scattering: strong interaction between the particle and the incident beam, although depending on particle refractive index. No simple relation between scattered intensity and particle diameter This leads to e.g. three different particle sizes for the scattering intensity of 10. The curve crosses y=10 three times. = particle circumference incident wavelength Webinar Aerosol Monitoring

The photo diode captures the scattering light under a narrow opening angle whereas the wide field

26 Handling the Mie scattering With our specific alignment of the optical components we smoothen out the Mie scattering problems. The photo diode captures the scattering light under a narrow opening angle whereas the wide field reflector offers 120 of opening angle to collect the different scattering intensities in order to reflect the sum signal back onto the photo diode Webinar Aerosol Monitoring

27 Indoor & Outdoor Monitoring & Webinar Aerosol Monitoring

Safety & Health Instruments typically used by HSEs: 11-C In safety & health applications often used GRIMM spectrometers - indoors and outdoors Values provided simultaneously PM10 PM2.

28 Safety & Health Instruments typically used by HSEs: 11-C In safety & health applications often used GRIMM spectrometers - indoors and outdoors Values provided simultaneously PM10 PM2.5 PM1 TSP Respirable TWA (PEL and action level) Count distribution to see HOW MANY particles enter the alveoli Particle surface to find out how much space particles offer toxics to attach MiniWRAS EDM164 Webinar Aerosol Monitoring

This device is in use world-wide and officially approved according to the US EPA

29 FEM Governmental Measurement Networks GRIMM Technologies equips governmental measurement networks with its EDM180 and EDM180+. This device is in use world-wide and officially approved according to the US EPA European Norms MCERTS CMA (Asia) All PM values simultaneously One device No consumables Webinar Aerosol Monitoring

30 Industry Heavy dust loads / mass Webinar Aerosol Monitoring

31 Research Automotive Jet engine / turbine Atmosphere / Troposphere Environmental studies Webinar Aerosol Monitoring

Dolomite calibration II Room or outdoor air

32 Calibration Of Instruments Preparing instruments and equipment for calibration Dolomite calibration I Dolomite calibration II Room or outdoor air calibration Validation Documentation Webinar Aerosol Monitoring

33 Calibration Of Instruments Grimm is using three different types of aerosols for calibration and validation processes based on it specific behaviours: 1) Latex (Polystyrene), monodisperse used for validation of certain size channels (candidate with reference) and set up of optical cell (mirror screw) before calibration 2) Dolomite, polydisperse used for calibration of all channels during the calibration process and calibration ramps for particle number and particle mass (PM values) before and after calibration procedure 3) Ambient air (urbane aerosol), polydisperse final validation of PM values Webinar Aerosol Monitoring

Calibration Of Instruments Massevergleich Raumluft Konzentration Referenzgerät [µg/m³] 7H100021 Datum: 29.07.13 Location: Turm 4 PM10: PM2.

0 µg Konzentration Prüfling [µg/m³] 8HG13049 Abweichung Prüfling PM10: PM2.5: PM1: PM10: PM2.

34 Calibration Of Instruments Massevergleich Raumluft Konzentration Referenzgerät [µg/m³] 7H Datum: Location: Turm 4 PM10: PM2.5: PM1: Ausführung: CS 34,9 20,3 12,0 Toleranz: max. +/- 3% oder max. +/- 2µg/m³ V= 0,0783 m³ t= 1,09 h Mass comparison Tolerance: ± 3 % or ± 1.0 µg Konzentration Prüfling [µg/m³] 8HG13049 Abweichung Prüfling PM10: PM2.5: PM1: PM10: PM2.5: PM1: 34,7 20,1 12,1-0,57 % -0,99 % 0,83 % -0,2 µg/m³ -0,2 µg/m³ 0,1 µg/m³ V= 0,0783 m³ t= 1,09 h Ambient air (24 h average values) Tolerance: ± 3 % or ± 1.0 µg 24h-Average 87G09058 Ref 8HG11090 Can Deviation [%] PM % / 0.1 µg PM % / 0.1 µg PM % / 0.2 µg Webinar Aerosol Monitoring

35 Questions & Anwers Webinar Aerosol Monitoring

36 We appreciate your time Thank you for attending this Webinar. If you have any further questions, or want to configure your personal measurement solution together with our dedicated engineers, please do not hesitate to contact your local representative at RAECO or GRIMM Technologies directly. John Greivell Direct Dial: Cell: Fax: Corporate Office: 135 Bernice Dr. Bensenville IL Toll-Free: Achim Edfelder Headquarters GRIMM Aerosol Germany Bill Roe GRIMM Technologies, Inc. US office Phone: Fax: Office: P.O. Box 6358 Douglasville, GA Toll-Free: Webinar Aerosol Monitoring

37 Webinar Aerosol Monitoring

38 Validation Count comparison room air Tolerance: ± 3 % Countvergleich Raumluft Konzentration Referenzgerät [P/l] 7H Datum: Location: Turm Ausführung: CS Toleranz: max. +/- 3% bei > 300P/l V= m³ t= #WERT! h Konzentration Prüfling [P/l] 8HG13049 Abweichung Prüfling [%] ,97 1,79 2,23 2,90 2,54 2,60 1,78 2, ,13 2,02 1,26 0,75 0,14-0,87-3,63-5, ,98-11,29-11,29-10,34-12,50 0,00 0,00 0, ,00 #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! V= m³ t= #WERT! h Webinar Aerosol Monitoring

39 The EDM164 Smart heated sampling pipe Smart heater control unit Continuous pump for sample flow DustMonitor 164 Spectrometer GF-Version Power supply VAC &12 VDC Webinar Aerosol Monitoring

The EDM164 - benefits Fully automatic Portable 3 different PM s Maintenance free Extended memory Mobile monitoring Hot spot monitoring Public site monitor Source identification No radioactive source

40 The EDM164 - benefits Fully automatic Portable 3 different PM s Maintenance free Extended memory Mobile monitoring Hot spot monitoring Public site monitor Source identification No radioactive source Not critical to vibration Meteorological sensors (optional) Particle number distribution (optional) DC power for solar panel or truck Data logger for web access (optional) Webinar Aerosol Monitoring

41 The EDM164 performance vs US-EPA FEM monitor Grimm EDM 180 in mini container 31 channels 1.2 l/min PM10, PM2.5, PM1 dehumidification with isotherm nafion system Grimm DM 164 in weather housing 31 channels 1.2 l/min PM10, PM2.5, PM1 dehumidification with smart heater Webinar Aerosol Monitoring

42 The EDM164 PM10 correlation, real conditions vs. 164, PM10, a = 0,005%, N = PM10 [µg/m³] y = 0,7868x + 2,4813 R 2 = 0,822 The Grimm EDM164 shows a good correlation for lower PM10 concentrations and a minor underestimate for higher PM10 concentrations PM10 [µg/m³] Webinar Aerosol Monitoring

43 The EDM164 PM2.5 correlation, real conditions vs. 164, PM2.5, a = 0,005%, N = PM2.5 [µg/m³] y = 0,8431x - 0,1664 R 2 = 0,957 The Grimm EDM164 shows a very good correlation for all PM2.5 concentrations, especially again for the lower concentrations. With regard to primary standards for fine particles (generally referring to particles less than or equal to 2.5 micrometers (μm) in diameter, PM 2.5 ), EPA revised the level of the 24-hour PM 2.5 standard to 35 micrograms per cubic meter (μg/m 3 ) and retained the level of the annual PM 2.5 standard at 15μg/m Source: US-EPA website 180 PM2.5 [µg/m³] Webinar Aerosol Monitoring

44 The EDM164 PM1 correlation, real conditions vs. 164, PM1, a = 0,005%, N = PM1 [µg/m³] y = 0,85x - 0,5275 R 2 = 0,962 The Grimm EDM164 shows a very good correlation for all PM1 concentrations, especially again for the lower concentrations PM1 [µg/m³] Webinar Aerosol Monitoring

The EDM164 conclusion The EDM164 combines the world s most efficient and reliable EN & US-EPA approved light scattering technology for dust monitoring with a

45 The EDM164 conclusion The EDM164 combines the world s most efficient and reliable EN & US-EPA approved light scattering technology for dust monitoring with a smart heated dehumidification technology. reasonable in price high performance lowest maintenance lowest total cost of ownership Webinar Aerosol Monitoring

46 The Environmental Dust Monitor EDM180+ Webinar Aerosol Monitoring

47 Approvals EDM180+ PM10 - Approvals German Test at UMEG (EN12341, certified April 2008) Test-Sites: Karlsruhe, Stuttgart, Feldberg, Heidelberg Seasons: Summer- & Winterseason Reference: Low-Volume-Sampler Leckel, SEQ 47/50 Webinar Aerosol Monitoring

EQPM-0311-195, finished 2009) Test-Sites:

48 Approvals EDM180+ PM2.5 Approvals US EPA (Class III FEM Approval, EQPM , finished 2009) Test-Sites: Bakersfield (CA), Denver (CO), St-Louis (MI), New Haven (CT) Seasons: 2 Summer- & Winterseasons Set-up: 3 Candidates and 3 Reference instruments Webinar Aerosol Monitoring

Approvals EDM180+ Other Approvals & Equivalence Tests

Upcoming Tests: Germany Austria United Kingdom USA Russia

running at the moment Qual1, US-EPA Germany FI-HILLAMo

49 Approvals EDM180+ Other Approvals & Equivalence Tests Legal Approvals: Equivalence Tests: Running Tests: Upcoming Tests: Germany Austria United Kingdom USA Russia China CMA > 15 already passed successfully 7 tests are running at the moment Qual1, US-EPA Germany FI-HILLAMo US-EPA Be-ISSEP CN-CMA AT-UBA UK-MCert Webinar Aerosol Monitoring

50 Networks operating EDM180 / EDM180+ USA Austria Belgium Canada Croatia Chile Colombia China Finland Germany The Netherlands Japan Korea Mongolia Norway Poland Serbia Spain Czech Republic Many more Webinar Aerosol Monitoring

51 Detect, Measure, Analyze. Get Social with RAECO Blog.raeco.com

GRIMM Aerosol Spectrometer and Dust Monitors. Measuring principle

Grimm Aerosol-Technik GRIMM Aerosol Spectrometer and Dust Monitors Measuring principle Eng. Wolfgang Brunnhuber 1 Agenda Part A physical background general principles of optical particle detection Part