DRI STANDARD OPERATI NG PROCEDURE Page: 2 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### TABLE OF CONTENTS

Page

1 INTRODUCTION....................................................................................................... 7 1.1 Purpose of Procedure ...................................................................................................... 7 1.2 Measurement Principle ................................................................................................... 7 1.3 Measurement Interferences and Their Minimization...................................................... 8 1.4 Ranges and Typical Values of Measurements................................................................ 9 1.5 Typical Lower Quantifiable Limits, Precision, and Accuracy ..................................... 10 1.6 Personnel Responsibilities ............................................................................................ 11 1.7 Definitions for IMPROVE_A Therma l Protocol for Carbon Analysis ........................ 11 1.8 Related Procedures ....................................................................................................... 14 2 APPARATUS, INSTRUMENTATION, REAGENTS, AND FORMS.................... 15 2.1 Apparatus and Instrumentation..................................................................................... 15 2.1.1 Description.............................................................................................................. .. 15 2.1.2 Instrument Characterization...................................................................................... 21 2.1.3 Maintenance.............................................................................................................. 22 2.2 Spare Parts List ........................................................................................................... .. 22 2.3 Reagents................................................................................................................... ..... 25 2.3.1 Chemicals................................................................................................................ .. 25 2.3.2 Gases.................................................................................................................... ..... 25 2.4 Forms, Paperwork, and Logbook.................................................................................. 26 3 CALIBRATION PROCE DURES AND ST ANDARDS .......................................... 29 3.1 Instrument Calibration .................................................................................................. 29 3.1.1 End-of-Run Calibrations (Description) .................................................................... 29 3.1.2 Routine Calibrations (Description)........................................................................... 29 3.1.2.1 Automated Routine Calibration (Description & Instructions).......................... 29 3.1.2.2 Manual Routine Calibra tion (Instructions)....................................................... 31 3.1.3 Full Calibration (Description)................................................................................... 33 3.1.3.1 Preparation, Ranges and Traceability of Standards.......................................... 34 3.1.3.2 Calculating Calibration Slope........................................................................... 35 3.1.3.3 Typical Accuracy of Calibration Standards...................................................... 35 3.1.3.4 Data Treatment for Calibration Data ................................................................ 38 3.1.3.5 Calculations ...................................................................................................... 39 3.2 Instrument Calibra tion Instructions .............................................................................. 39 3.2.1 Full Gas Calibration.................................................................................................. 39 3.2.2 Full Sucrose and KHP Calibrations .......................................................................... 41 3.2.3 Temperature Calibrations ......................................................................................... 42 3.2.3.1 Temperature Indicators ..................................................................................... 42DRI STANDARD OPERATI NG PROCEDURE Page: 3 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2 

### TABLE OF CONTENTS, continued

Page 3.2.3.2 Analyzer Preparation ........................................................................................ 43 3.2.3.3 Standard Preparation......................................................................................... 43 3.2.3.4 Temperature Program ....................................................................................... 43 4 PROCEDURES ......................................................................................................... 47 4.1 Detailed Procedures ...................................................................................................... 47 4.1.1 Analyzer Start-Up ..................................................................................................... 47 4.1.2 Leak Checks.............................................................................................................. 48 4.1.2.1 Manual Leak Check .......................................................................................... 48 4.1.3 Oven Bake................................................................................................................ . 50 4.1.3.1 Manual Oven Bake ........................................................................................... 50 4.1.3.2 Automatic Oven Bake....................................................................................... 50 4.1.4 OC/EC Analysis........................................................................................................ 52 4.1.4.1 Analysis Preparation ......................................................................................... 52 4.1.4.2 Loading the Filter Punch................................................................................... 53 4.1.4.3 Post-Analysis .................................................................................................... 53 4.1.5 Special Analyses ....................................................................................................... 58 4.1.5.1 System Blanks................................................................................................... 58 4.1.5.2 Carbonate Analysis ........................................................................................... 60 4.1.6 Analyzer Shut-Down ................................................................................................ 60 4.2 Abbreviated Procedures................................................................................................ 61 4.2.1 Analyzer Start-Up ..................................................................................................... 61 4.2.2 Leak Checks and Oven Baking................................................................................. 62 4.2.3 OC/EC Analysis........................................................................................................ 63 4.2.3.1 Analysis Preparation ......................................................................................... 63 4.2.3.2 Loading the Filter Punch................................................................................... 63 4.2.3.3 Post Analysis..................................................................................................... 64 4.2.4 Special Analyses ....................................................................................................... 64 4.2.4.1 System Blanks................................................................................................... 64 4.2.4.2 Carbonate Analysis ........................................................................................... 64 4.2.5 Analyzer Shut-Down: ............................................................................................... 65 5 QUANTIFICATION ................................................................................................. 66 5.1 Measurement Calculations............................................................................................ 66 5.2 Precision (Uncertain ty) Calculations............................................................................ 66 6 QUALITY CONTROL ............................................................................................. 67 6.1 Performance Testing ..................................................................................................... 67 6.2 Reproducibility Testing ................................................................................................ 68 6.3 Control Charts and Procedures ..................................................................................... 68 6.4 Data Validation ............................................................................................................ . 69DRI STANDARD OPERATI NG PROCEDURE Page: 4 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2 

### TABLE OF CONTENTS, continued

Page 6.4.1 Analysis Flags........................................................................................................... 69 6.4.2 Daily Validation........................................................................................................ 7 0 6.4.2.1 Validation of Final Data File ............................................................................ 74 7 REFERENCES.......................................................................................................... 81 8 CHANGE DOCUM ENTATION .............................................................................. 83 APPENDIX A: Abbreviations and Acronyms............................................................................. 84DRI STANDARD OPERATI NG PROCEDURE Page: 5 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### LIST OF TABLES
Page Table 6-1. Common DRI Analysis Flags..................................................................................... 70 Table 6-2. DRI Carbon Analysis Operator Temporary Data Validation Flags. .......................... 78 Table 6-3. DRI Carbon Analysis Validation Comments ............................................................. 79DRI STANDARD OPERATI NG PROCEDURE Page: 6 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### LIST OF FIGURES

Page Figure 2-1. DRI Model 2001 Thermal/Optical Carbon Analyzer. .............................................. 16 Figure 2-2. DRI Model 2001 Thermal/Optical Carbon Analyzer Schematic Diagram............... 17 Figure 2-3. DRI Model 2001 Thermal/Optical Carbon Analyzer Sealing Diagram. .................. 18 Figure 2-4. DRI Model 2001 Thermal/Optical Carbon Analyzer Gas Flow Schematic. ............ 19 Figure 2-5. DRI Model 2001 Thermal/Optical Carbon Analyzer Combustion Oven. ................ 20 Figure 2-6. DRI Carbon Analysis Logbook Format. ................................................................... 23 Figure 2-7. DRI Carbon Sample Analysis Run List. ................................................................... 27 Figure 2-8. DRI Carbon Daily Analyzer Checklist. .................................................................... 28 Figure 3-1. Calibration thermogram from the cmdAutoCalibCheck command of the DRI Model 2001 Thermal/Optical Carbon Analyzer. .................................................................. 30 Figure 3-2. Setup Screen for Manual Gas Calib ration for the DRI Model 2001 Thermal/Optical Carbon Analysis Program.......................................................................................... 32 Figure 3-3. The Analysis Screen duri ng Manual Gas Calibration for DRI Model 2001 Thermal/Optical Carbon Analysis Program. ............................................................. 33 Figure 3-4. Example of calibration summary worksheet used to determine calibration slope.... 36 Figure 3-5. Example DRI Carbon Analyzer Calibration Curves................................................. 37 Figure 3-6. Temperature ramping with a Temp ilaqo G temperature indicator rated at 184 ° C. Also shown are reflectance and transmitta nce of the temperature indicator (if available). The vertical dashed line i ndicates the achievement of the rated temperature................................................................................................................ 45 Figure 3-7. Reflectance and transmittance measurem ents and their first and second derivatives over time with a Tempilaqo G temperature indicator rated at 184 ° C (Figure 3-6). The vertical dashed line indicates the achievement of the rated target temperature. 46 Figure 4-1. DRI Welcome Screen................................................................................................ 49 Figure 4-2a. Setup Screen for the DRI Model 2001 Thermal/Optical Carbon Analysis Program..

.............................................................................................................................. ..... 54 Figure 4-2b. The Analysis Screen during Sample Analysis for DRI Model 2001 Thermal/Optical Carbon Analysis Program.......................................................................................... 55 Figure 4-3. Tabular Printout from DRI Mode l 2001 Thermal/Optical Carbon Analysis Program.

.............................................................................................................................. ..... 56 Figure 4-4. Graphical output (thermogram) from the DRI Model 2001 Thermal/Optical Analysis Program. .................................................................................................................... 59 Figure 6-1. Example of carbon an alyzer replicat e checklist........................................................ 69DRI STANDARD OPERATI NG PROCEDURE Page: 7 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 1 INTRODUCTION

1.1 Purpose of Procedure

This standard operating procedure is intended to:

• Provide a basic understanding of the principl es of carbon analysis and carbon analyzer operation;

• Describe routine determination of organi c, elemental, and carbonate carbon from ambient- and source-filter samples using the DRI Model 2001 Thermal/Optical Carbon Analyzer; and

• Detail the concerns and procedures which will ensure a state-of-the-art carbon analysis measurement process.
This procedure will be followed by all analysts at the Environmental Analysis Facility (EAF) of the Division of Atmospheric Sciences (DAS) at the Desert Research Institute (DRI), Reno, Nevada, USA.

1.2 Measurement Principle

The operation of the DRI Model 2001 Thermal/O ptical Carbon Analyzer is based on the preferential oxidation of organic and elemen tal carbon (OC and EC) compounds at different temperatures. Its function relies on the fact th at organic compounds can be volatilized from the sample deposit in a non-oxidizing helium (He) atmos phere, while EC must be combusted with an oxidizer. The analyzer operates by: 1) liber ating carbon compounds under different temperature and oxidation environments from a small sample punch taken from a quartz-fiber filter; 2) converting these compounds to carbon dioxide (CO 2 ) by passing the volatilized compounds through an oxidizer (heated manganese dioxide, MnO 2 ); 3) reducing CO 2 to methane (CH 4 ) by passing the flow through a methanator (hydrogen-en riched nickel catalyst); and 4) quantifying CH 4 equivalents with a flame ionization detector (FID).

The principal function of the optical (laser reflectance and transmittance) component of the analyzer is to correct for pyrolysis charring of OC compounds into EC. Without this correction, the OC fraction of the sample might be underes timated and the EC fraction might include some pyrolyzed OC. The correction for pyrolysis is made by continuously monitoring the filter reflectance and/or transmittance (via a He-n eon laser and a photo-detector) throughout an analysis cycle. The reflectance and transmittan ce, largely dominated by the presence of light absorbing EC, decrease as pyrolysis takes place and increase as light-absorbing carbon is liberated during the latter part of the analysis. By monitoring the reflectance and transmittance,DRI STANDARD OPERATI NG PROCEDURE Page: 8 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
the portion of the EC peak corresponding to pyroly zed OC can be accurately assigned to the OC fraction. The correction for the charring conversion of OC to EC is essential for a less-biased measurement of carbon fractions (Johnson et al., 1981). The Thermal Optical Reflectance (TOR) and Thermal Optical Transmittance (TOT) charri ng corrections are not necessarily the same, owing to charring of organic vapors adsorbed w ithin the quartz fiber filter (Chow et al., 2004; Chen et al., 2004). Charring by both reflectance and transmittance is reported in order to determine the differences in OC and EC.

Carbonate carbon can be determined by measuring the CO 2 evolved upon acidification of the sample punch before the normal carbon analysis procedure.

Seven temperature fractions, as well as the TO R and TOT charring correction, are individually quantified and reported when the IMPROVE _A (Chow et al., 1993, 2001, 2007) temperature protocol is applied. Values routinely reported include total OC, total EC, total carbon (TC, sum of total OC and total EC), and pyrolyzed carbon, monitored by both reflectance (OPR) and transmittance (OPT). Depending on the thermal/optical protocol applied for quantification, thermally-derived subfractions of OC and EC, and of carbonate carbon, are reported.

1.3 Measurement Interferences and Their Minimization

Precision of thermal/optical carbon analysis depends on the sample temperature in the analysis. Therefore, the correlation between sample temperature and thermocouple temperature should be established and calibrated semiannually so that the thermal protocol can truly reflect the sample temperature during the analysis (Chow et al., 2005). The thermocouple’s position in relation to the sample, as well as the different heating properties of the thermocouple and the sample, govern the temperature offset. This relations hip must be maintained for the temperature calibration to hold. The analyzer must not be us ed if the sample boat shifts position or becomes loose in its holder.

Carbonate carbon may bias carbon concentrations if it constitutes more than 5% of TC in the ambient or source sample. Carbonate carbon may be measured as either OC or EC depending on the chemical nature of the carbonates and thei r thermal decomposition temperatures. Acid pretreatment of filter samples can elimin ate the carbonate interference (Novakov, 1981, 1982; Rosen et al., 1982). Carbonate carbon has been found at only a few IMPROVE monitoring sites, and the levels at these sites do not appreciably bias OC and EC concentrations (Chow and Watson, 2002).

The presence of certain minerals in some soils can affect the laser correction for pyrolysis. These minerals change color as the sample punch is heated, generally resulting in a darker sample. For samples which contain large fracti ons of resuspended soils, the split between OC and EC should be examined manually.DRI STANDARD OPERATI NG PROCEDURE Page: 9 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Some minerals, again predominantly in soil samp les or soil-dominated samples, may affect the laser correction by temporarily changing color or changing the surface texture of the depositresidue. Unlike the effect described above, these changes are reversible and temperaturedependent.

Some colored organic compounds can affect th e laser correction, causing increased reflectance or decreased transmittance as these compounds are removed. This effect is ascertained by examining the laser response during the organic portion of the analysis. The split between OC and EC should be examined manually if the effect is large.

The presence of certain elements (Na, K, V, Cr , Mn, Co, Ni, Cu, and Pb), existing either as contaminants on the filters (e.g., glass-fiber filters or borosilicate binders), or as part of the deposit material, has been shown to catalyze the removal of EC at lower temperatures (Lin and Friedlander, 1988). Such catalysis would aff ect the distribution of carbon peaks during the analysis.

Water vapor (either contained in the deposit or remaining after acidification of the sample punch), if present in sufficient leve ls, can shift the FID baseline. To eliminate this effect, allow the sample punch to dry in the analyzer by pa ssing carrier gases over it before starting the analysis.

1.4 Ranges and Typical Values of Measurements

Source-dominated or heavily polluted envi ronments, which would normally have carbon concentrations above the working range of th e carbon analyzer, may be sampled and analyzed within the range of the carbon analyzer by incr easing the filter deposit area or by decreasing the sampling flow in the field equipment. Deposits that are very black, such that the initial reflectance is close to zero, provide a less preci se OC/EC split, because additional blackening due to OC charring is not quantified by the reflected light.

The carbon analyzer can effectively measure between 0.05 and 750 μg carbon/cm 2 for a typical punch size of 0.5 cm 2 . The upper limit depends on the particular compounds on the filter and the temperatures at which they evolve. This upper limit may be extended by reducing the punch size or extending analysis times at lower temperature plateaus to avoid an over-range FID signal.

Typical carbon values range between 10 and 100 μg C/cm 2 for 24-hour ambient samples. The distribution between OC and EC depends on the particulate source types, ranging from negligible levels of EC (e.g., secondary sulfate) to 80% or more EC (e.g., diesel exhaust).DRI STANDARD OPERATI NG PROCEDURE Page: 10 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

1. 5 Typical Lower Quantifiable Limits, Precision, and Accuracy

The lower quantifiable limits (LQLs) of thermal carbon methods depend on the variable carbon content of the field blank quartz-fiber filters, as well as the analysis method. For lower LQLs, the unexposed filters should be pre-fired in an oven at high temperatures for several hours to remove any residual carbon contamination (Fung, 1986; Huntzicker, 1986; Rau, 1986; DRI, 2004). All quartz-fiber filters originating from DRI are pre-inspected for defects such as pinholes or tears. They are then pre-fired for a minimum of four hours at 900 °C; 2% are acceptance-tested for blank levels before use in the IMPROVE network. Batches containing filters that fail to pass the preset acceptance le vels (1.5 μg OC, 0.5 μg EC, and 2.0 μg TC per

cm 2 ) are not used for sample collection. Aver age pre-fired blank levels are 0.15 ± 0.15 μg OC/cm 2 , 0.00 ± 0.02 μg EC/cm 2 , and 0.15 ± 0.15 μg TC/cm 2 . Because pre-fired filters can adsorb organic vapors during shipping, storage, a nd exposure in the sampler, the analysis LQL on a particular set of filters depends on the number of field blanks analyzed and the variability in the results from those blanks. LQLs may vary between projects, depending on the sample and sample handling. To reduce the risk of contam ination during shipping and storage, samples are vacuum-sealed and stored at < 4 °C. The v acuum sealing results in minimum air space surrounding the filter to ensure the blank levels are kept low.

The minimum detection limits (MDLs) represent the best sensitivity of the method and should always be less than or equal to the LQLs. The IMPROVE_A protocol is based on the analyses of approximately 800 pre-fired laboratory blank quart z-fiber filters analyzed between January 2006 and May 2007. The MDL is defined as three times the standard deviation of their measured results. They are:

total OC 0.39 μg/cm 2

total EC 0.01 μg/cm 2

TC 0.42 μg/cm 2

Acid-evolved carbonate levels in pre-fired quartz- fiber filters have been shown to be quite variable (0.0-1.0 μg/cm 2 ) over time. The reaction of ambient CO 2 with alkaline sites on the quartz fibers may be the cause of such variable blank levels. Acceptance testing for carbonate is only performed for special projects that require carbonate analysis.

The precision of carbon analysis has been repor ted to range from 2 – 4% (Johnson, 1981). For analysis of actual ambient and source filters, homogeneity of the deposit is most important for reproducible results. This can be demonstrated by the precision of CH 4 standard injection (by the Carle valve), which is always better than sample analysis. For homogeneous deposits containing > 5 μg/cm 2 (~10 times MDL) TC, precision is generally 10% or better; for inhomogeneous deposits replicates may differ by as much as 30%. The precision of carbonate concentrations is approximately ±10%.DRI STANDARD OPERATI NG PROCEDURE Page: 11 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
The precision of the laser-dependent split be tween OC and EC fractions depends upon how rapidly the laser is increasing at the time of th e split and whether or not the split falls in the middle of a large carbon peak. Typically, relativ e laser split times are reproducible within 10 seconds and deviations in calculated splits are < 5% of the total measured carbon. If the laser split is greater than 10 seconds and deviations are > 5%, the analysis is investigated for sample anomalies (e.g., inhomogeneous loading, low load ing, etc.), instrument laser noise, or O 2 contamination.

The accuracy of TOR for TC, determined by an alyzing a known amount of carbon, is between 2- 6% (Rau, 1986). Precision of the OC/EC split is between 5% and 10%. This precision is also influenced by the filter loading and source type. Most of the uncertainty for low concentration samples is from the standard deviation of the fi eld blanks or backup filters. Uncertainty is not determined by precision at low levels.

Since the MDL is always less than or equal to the LQL, and the LQL is included in the μg/m 3 uncertainty when the blank (or backup filter, if available) is subtracted, the MDL has no effect on the uncertainty of ambient concentrations. Th e MDL is most useful to match flow rates and sample duration with expected carbon levels when planning field studies or sampling networks.

1.6 Personnel Responsibilities

Before performing carbon analysis, all analysts in the laboratory should read and understand the entire Standard Operating Procedure (SOP), incl uding routine system calibration, actual analysis, and immediate review of the data as it is produced, and how to correct system problems.

The responsibilities of the laboratory manager or supervisor are: to ensure that the carbon analyses procedures are properly followed; to ex amine and document all replicate, standard, and blank performance test data; to designate sample s for reanalysis; to arrange for maintenance and repair of instruments; to verify an adequate qua ntity of supplies and gases are in stock to ensure uninterrupted analysis; and to deliver the analys is results in database format to the project manager within the specified time period.

The quality assurance (QA) officer of DRI's DAS is responsible for determining the extent and methods of quality assurance to be applied to each project, to estimate the level of effort involved in this quality assurance, to periodi cally review and assess quality assurance and quality control data, to update this procedure peri odically, and to ascertain that these tasks are budgeted and carried out as part of the performance on each contract.

1.7 Definitions for IMPROVE_A Thermal Protocol for Carbon Analysis

The following terms are used in this document:DRI STANDARD OPERATI NG PROCEDURE Page: 12 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

IMPROVE_A Thermal Protocol: A thermal protocol used in carbon analyzers to quantify carbon fractions evolved at different temp erature plateaus and atmospheres. The IMPROVE_A thermal protocol derives from the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal protocol initiated in 1987 (Chow et al., 2005, 2007).

Calibration Injection: The injection of calibration gases, either CO 2 or CH 4 , into the sample stream at the beginning a nd end of each work day to check instrument performance.

Calibration Peak: The FID peak resulting from the automatic injection of methane calibration gas (CH 4 /He) at the end of each analysis run for each sample. All integrated peak areas are divided by the calibration peak area and multiplied by an instrument-specific calibration factor to obtain μg carbon per sample punch.

FID Split Time: The time at which the laser split occurs plus the transit time required for thermally evolved carbon to trav el from the sample punch to the FID.

Elemental Carbon (EC): Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere at 580, 740, and 840 °C minus any pyrolyzed OC.

EC1: Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere at 580 °C.

EC2: Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere from 580 to 740 °C.

EC3: Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere from 740 to 840 °C.

High Temperature OC: Carbon evolved from th e filter punch in a He-only atmosphere at 280, 480, and 580 °C plus pyrolyzed organic carbon. This is OC minus the first OC peak (OC1).

High Temperature EC: Carbon evolved fr om the filter punch in a 98% He/2% O 2 atmosphere at 740 and 840 °C mi nus any pyrolyzed organic carbon present in these two peaks. This is EC minus the first EC peak (EC1).DRI STANDARD OPERATI NG PROCEDURE Page: 13 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Laser Split: The separation between OC and EC, which depends on the lasermeasured reflectance and/or transmittance of the filter punch returning to its initial value. At th is point all pyrolyzed OC has been removed and EC is beginning to evolve.

Lower Split Time: The time at which the laser-measured reflectance and/or transmittance of the filter punch r eaches its initial value minus the precision of the laser signal (currently defined as 10 counts).

Organic Carbon (OC): Carbon evolved from the filter punch in a He-only (> 99.999%) atmosphere at 140, 280, 480 and 580 °C plus pyrolyzed organic carbon. This is the same as Volatile Organic Carbon (VOC) plus high-temperature OC.

OC1: Carbon evolved from the f ilter punch in a He-only (> 99.999%) atmosphere from ambient (~25 °C) to 140 °C.

OC2: Carbon evolved from the f ilter punch in a He-only (> 99.999%) atmosphere from 140 to 280 °C.

OC3: Carbon evolved from the f ilter punch in a He-only (> 99.999%) atmosphere from 280 to 480 °C.

OC4: Carbon evolved from the f ilter punch in a He-only (> 99.999%) atmosphere from 480 to 580 °C.

OP: The carbon evolved from the time that the carrier gas flow is changed from He to 98% He/2% O 2 at 580 °C to the time that the laser-measured filter reflectance (OPR) or transmittance (OPT) reaches its initial value. A negative sign is assigned if the laser split occurs before the introduction of O 2
. Pyrolysis: The conversion of OC compounds to EC due to thermal decomposition; this may be envi sioned as "charring" during the organic portion of the analysis.

Regular Split Time: The time at which the laser-measured reflectance and/or transmittance of the filter punch reaches its initial value.

Total Carbon (TC): All carbon evolved from the filter punch between ambient and 840 °C under He and 98% He /2% O 2 atmospheres.

Upper Split Time: The time at which the laser-measured reflectance and/orDRI STANDARD OPERATI NG PROCEDURE Page: 14 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
transmittance of the filter punch r eaches its initial value plus the precision of the laser signal (currently defined as 10 counts).

1.8 Related Procedures

Standard Operating Procedures (SOPs), related carbon analysis activities, and other manuals that should be reviewed in conjunction with this document are:

DRI SOP #6-001 Shipping and Mailing SOPs.

DRI SOP #6-009 Field and Laboratory Safety SOPs.

DRI SOP #2-106r6 Pre-Firing of Quartz Filters for Carbon Analysis.

The DRI Model 2001 Thermal/Optical Carbon Analyzer Owner's Manual , revised 3/2004 (Atmoslytic, Calabasas, CA).

The DRI Model 2001 Thermal/Optical Carbon Analyzer Installation, Operation and Troubleshooting Manual , revised 12/2004 (Atmoslytic, Calabasas, CA).DRI STANDARD OPERATI NG PROCEDURE Page: 15 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 2 APPARATUS, INSTRUMENTATION, REAGENTS, AND FORMS

2.1 Apparatus and Instrumentation

2.1.1 Description

The components of the DRI Model 2001 Thermal/O ptical Carbon Analyzer are depicted in Figures 2-1 through 2-3; the complete gas flow sc hematic is shown in Figure 2-4. Other details of the configuration of the DRI Model 2001 Therma l/Optical Carbon Analyzer are referred to in the owner's manual. The programmable combusti on oven is the heart of the carbon analyzer and includes loading, combustion, and oxidation zones in a single quartz "oven" as depicted in Figure 2-5.

In addition to the DRI Model 2001 Thermal/Optical Carbon Analyzer, which is connected to a Pentium compatible computer, the following items are needed for routine carbon analysis:

• Stainless steel punching too l: 5/16-inch diameter, 0.5 cm 2 nominal area for removing small sample punches from quartz filters. This punching tool must be kept clean and sharp. If the punching tool is resharpe ned, the punch area must be re-verified. Verification is performed by removing 10 punches from a 47-mm quartz-fiber filter (17.35 cm 2 ); then calculating the punch area [= 17.35 cm 2 x (initial filter weight minus the final weight after punches have been rem oved) / 10 times the initial filter weight)]. Further verification can be done by taking a precise measurement of the punching tool.

• Syringes: Hamilton Gas-Tight 1000 and 2500 μl syringes for calibration injections; 25 μl syringe for carbonate analysis and for analyzer calibration.

• Quartz filters: Pallflex® Tissuquartz, 2500 QAT -UP (Pall Life Sciences, Ann Arbor, MI) quartz-fiber filter or equivalent.

• Flat-tip tweezers.

• Flat glass plate.

• Logbook/notebook.

• Transparent tape.

• KIMTECH Pure* CL4 Critical Task Wipes and large KimWipes (EX-L).

• Small Styrofoam cooler or refrigerator.DRI STANDARD OPERATI NG PROCEDURE Page: 16 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 2-1. DRI Model 2001 Thermal/Optical Carbon Analyzer.DRI STANDARD OPERATI NG PROCEDURE Page: 17 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 2-2. DRI Model 2001 Thermal/Optical Carbon Analyzer Schematic Diagram.

Temperature M onito r He O 2 / He CH 4 / He

Valve Network

Sample Port Sample Oven Lase r

Photo Detector

Oxidation

Oven Methanator FID

Microcomputer FID Signal

Reflectance/ Transmittance Signal Oven Control

Gas Flow Control H 2 Air

Disk Files Display Printer Ga Control

s StreamDRI STANDARD OPERATI NG PROCEDURE Page: 18 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 2-3. DRI Model 2001 Thermal/Optical Carbon Analyzer Sealing Diagram.

Note: In the breech, there is a Teflon-reducing ferrule to seal the pushrod thermocouple, plus two O-rings to seal the breech against the in let (coupler) connector and one Teflon fitting (See the Model 2001 Owner’s Manual for more details).DRI STANDARD OPERATI NG PROCEDURE Page: 19 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 2-4. DRI Model 2001 Thermal/Optical Carbon Analyzer Gas Flow Schematic.DRI STANDARD OPERATI NG PROCEDURE Page: 20 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 2-5. DRI Model 2001 Thermal/Optical Carbon Analyzer Combustion Oven.DRI STANDARD OPERATI NG PROCEDURE Page: 21 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Blue ice (if using Styrofoam cooler).

• Butane or piezoelectric lighter.

• A copy of DRICarb.exe (the analysis program), Carbon.par (the analysis parameter file), and Microsoft Access to run CarbonNetWork.mdb

.
2.1.2 Instrument Characterization

The DRI Model 2001 Thermal/Optical Carbon Anal yzer is program-driven. Data is stored automatically to the hard drive via a PC-compa tible computer processor board. Response times and signal lag times are built into the parameter f ile that is loaded when the analysis program begins. The program is driven by the ther mal protocol. For example, when using the IMPROVE_A protocol, the program will advance to the next temperature or carrier gas mixture once the FID signal returns to its baseline; i.e., after a minimum of 150 seconds at one analysis condition. A maximum time limit (580 seconds) per analysis condition is also established to prevent a slight baseline drift from holding the an alyzer in one condition indefinitely. For the Chemical Speciation Network (CSN, in cluding the Speciation Trends Network [STN]) thermal protocol, the program advances from one specified temperature plateau to the next temperature or carrier gas mixture when the specified analysis time is reached. Both methods require at least one ~0.5 cm 2 punch per filter and do not require sample pre-treatment. The sample punch is destroyed by both methods.

Operator concerns for correct routine operation of the instrument include the following (refer to Section 4 for more details):

• Verify sample oven pressure reading and speci fied flow range in the front-panel flow
meters.

• DO NOT leave the room until the analysis begins.

• Check the graphical printout after each analys is run to ensure that the: 1) FID, 2) temperature, and 3) laser signals are beha ving as expected (Section 3.1). Report any anomalies to the lab supervisor immediately.

• The quartz oven is susceptible to breakage. Care should be taken when handling and cleaning.

• Be careful that no fiber from the KIMTECH wipe is left on the sample punch, tweezers, and/or glass plate.DRI STANDARD OPERATI NG PROCEDURE Page: 22 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

2.1. 3 Maintenance

Regular maintenance for the analyzer involves daily checking of compressed gas supplies, cleaning the punching tool and tweezers between each sample with dry KIMTECH wipes, ensuring that the lab is clean, and backing up data files to disc on a daily basis (unless files are automatically backed up to server). Temperatur e calibrations for the six temperature plateaus (140, 280, 480, 580, 580, 740, and 840°C) need to be performed semiannually (see details in Section 3.2.3). Checks of laser adjustments and l eaks are made at least monthly or on an as needed basis. The procedure for leak checks can be found in Section 4.1.2. Additional leak tests are performed with a He leak detector each time a part is replaced, or whenever the analyzer fails the leak check during the daily routine. The sy stem should show no He leaks at the various connections of the quartz cross oven. Since He ha s high diffusivity, freedom from He leaks will safeguard against O 2 diffusion into the system. These O 2 levels are determined semi-annually using a gas chromatography/mass spectrometry (GC/ MS) instrument on the analyzer. Quarterly levels are determined using an O 2 detector that is calibrated against the GC/MS. This is also used when a fresh He cylinder is installed to assure the quality of the gas supply and the condition of the O 2 scrubber. If the cmdAutoCalibCheck command is used for calibration, the condition of the catalysts will be indicated and a ppropriate action can be taken (such as catalyst replacement). All calibrations, repairs, and check s must be recorded in the Carbon Analyzer Logbook (Figure 2-6). Flow rates of all operati ng gases should be checked and adjusted (if needed) whenever a new quartz oven or methanator is installed or serviced. Additionally, a flow check and balance should be performed as well.

2.2 Spare Parts List

The following spare parts must be kept on hand to ensure minimal interruptions in carbon analysis:

• Quartz furnace tube available from the manufacturer (Atmoslytic, Calabasas, CA).

• Quartz rods: 3 mm nominal diameter, opti cal quality (Atmoslytic, Calabasas, CA), polished for optical clarity with 104 mm (upper arm) and 119 mm (lower arm) lengths. The version of the carbon analyzer manufact ured in 2001 uses a 98 mm rod for the upper arm. Measure the old rods for reference.

• Catalyst ovens: Watlow 15.24 cm length, 2.54 cm tube diameter element from the analyzer supplier.

• Quartz boats (Atmoslytic, Calabasas, CA).

• Quartz wool: For repacking the oxidation oven (Alltech Associates, #4033, Deerfield, IL).DRI STANDARD OPERATI NG PROCEDURE Page: 23 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 2-6. DRI Carbon Analysis Logbook Format.DRI STANDARD OPERATI NG PROCEDURE Page: 24 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Thermocouple rods: 24.13 cm length by 0.32 cm outside diameter (OD), Type-K ground isolated with Inconel sheath (Omega, Pa rt #TJ36-CAIN-18E-9.5, Stamford, CT). Remove 1 cm of the sheath with a file to obtain the longer tip needed in this application.

• FID flame tips: for Gow-Mac #12-800 FIDs (Gow-Mac, #132-117, Bethlehem, PA).

• Septa: Standard 0.32 cm or 0.64 cm cylindri cal (Alltech Associates #6524, Deerfield, IL) for injection ports. Silicon septa 0.25 cm and 1.11 cm for oven seals (Alltech #15427 and #15429, Deerfield, IL).

• 1 ml gas tight syringe for gas injections.

• 25 μl syringes for liquid injections.

• Replacement needles for syringes (Alltech #7729-06, Deerfield, IL).

• Replacement oxygen/moisture trap (R&D Se parations, Model OT3-2, Rancho Cordova, CA).

• Replacement hydrocarbon trap (R&D Sepa rations, Model HT200-4, Rancho Cordova, CA).

• Replacement indicating oxygen trap (Chrom atography Research Supplies, Model 202223, Louisville, KY).

• Viton O-rings: Size 013. Two needed for quartz oven tube inlet.

• Teflon ferrules: Parker or Swagelok style 0.64 cm front and back ferrule for the quartz oven tube outlet connections (Swagelock, T- 400-SET, Solon, OH). Refer to instrument user manual for specific ferrule sizes.

• Teflon ferrules: 0.32 cm to 0.64 cm (Alltech Associates, #RF-400/200-T, Deerfield, IL), for the thermocouple rod at the inlet breech. Re fer to instrument user manual for specific ferrule sizes (style varies by location on analyzer).

• High temperature silicone seals for quartz light rods and connector, prepared by Alltech Associates, #15427 and #15429, Deerfield, IL.

• Heating element for oven (Watlow, #VC 401A06A-0000R [90° bend], Columbia, MO).

• Printer paper and toner cartridge.

• Computer CD for backup if not on server backup.DRI STANDARD OPERATI NG PROCEDURE Page: 25 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

2. 3 Reagents

2.3.1 Chemicals

The following chemicals should be reagent grade or better:

• Potassium hydrogen phthalate (KHP), for calib ration (Fisher Scientific, cat #P-243, CAS 877-24-7, Fairlawn, NJ).

• Sucrose, for calibration use (EM Science, #SX1075-1, Gibbstown, NJ).

• Manganese dioxide (MnO 2 ), crystalline, as an oxidizer in the oxidation oven (Nurnberg Scientific, #C5162, Portland, OR; Aldrich Chemicals #24344-2, St. Louis, MO; or equivalent).

• Nickelous nitrate [Ni(NO 3 ) 2 ·6H 2 O], crystalline, used to prepare the nickel catalyst in the methanator (Fisher Scientific, cat #N62-5000, CAS 13478-00-70, Fairlawn, NJ).

• Chromosorb A, 20/30 mesh, used as a support fo r nickel catalyst in the methanator (from any chromatography supplier, such as Alltech cat #2-0165). Both nickelous nitrate and Chromosorb A are for preparing the reduction catalyst in the methanator.

• Hydrochloric acid (HCl), 0.4 molar solution, for use in cleaning punch and quartz ovens, and for use in carbonate analysis (Fis her Scientific, cat #A508-212, CAS 7647-01-0, Fairlawn, NJ).

• Hydrofluoric acid (HF), diluted to 15% ma y be used for removing the white deposits from devitrification (white deposits of SiO 2 ) on the quartz oven parts (Fisher Scientific, cat #A147-1LB, CAS 7664-39-3, Fairlawn, NJ). However, proper safety precautions must be followed when using HF and quartz oven parts may become brittle with repeated

use.

• Nanopure water (used as described in Section 3.1.3.1).

2.3.2 Gases

The following gases should be ultra-high purity (UHP) grade or better:

• He for a carrier gas, regulated to 15-40 psi with a metal diaphragm regulator. The higher pressure is required due to the pressure drop across the Supelco oxygen scrubber.

• 5% CH 4 by volume in He for calibration injections and calibration peaks; regulated to 10 psi by a metal diaphragm regulator.DRI STANDARD OPERATI NG PROCEDURE Page: 26 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• 5% CO 2 by volume in He for calibration injec tions; regulated to 10 psi by a metal diaphragm regulator.

• 10% O 2 by volume in He as a carrier gas, regulated to 15 psi by a metal diaphragm regulator.

• Hydrogen for the FID flame, regulated to 15 psi with a metal diaphragm regulator.

• Hydrocarbon-free air to supply O 2 to the FID, regulated to 15 psi by a metal diaphragm regulator from a zero air generator.

• Compressed air for pneumatic activation, regulated to ~25 psi.

At least one backup cylinder per gas type shoul d be kept on hand at all times. Depending on analysis volume, the 90% He/10% O 2 mixture are typically replaced every four to six weeks; H 2 and He are replaced once a week. All gases are replaced when the cylinder pressure drops below 500 psi (unless the cylinders are connected to an automatic change-over module). Check the O 2 scrubber and follow the manufacturer’s recommendations for scheduling its replacement.

The flow settings on the flow meters (rotameters) are based on an input of 15 psi for He, 90% He/10% O 2 , H 2 , and FID air. The pneumatic drivers fo r the breech should have a pressure of ~25 psi to operate effectively (sealing the opening).

2.4 Forms, Paperwork, and Logbook

All samples are logged in upon receipt at the laboratory. A sample analysis list will be prepared by the laboratory supervisor or designated techni cian indicating which samples will be analyzed, plus any special instructions. As individual samp les are analyzed, entries are made in the Carbon Analyzer Logbook, as shown in Fi gure 2-6. Figure 2-7 provides an example of the cover sheet of the sample analysis run list. Figure 2-8 pr ovides an example of the Daily Analyzer Checklist that is completed at the start of each day in order to verify analyzer flow and FID response.DRI STANDARD OPERATI NG PROCEDURE Page: 27 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 2-7. DRI Carbon Sample Analysis Run List.DRI STANDARD OPERATI NG PROCEDURE Page: 28 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 2-8. DRI Carbon Daily Analyzer Checklist.DRI STANDARD OPERATI NG PROCEDURE Page: 29 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 3 CALIBRATION PROCEDURES AND STANDARDS

3.1 Instrument Calibration

The calibration procedures for the carbon analy zers are of four types: 1) the end-of-run calibration peak; 2) the routine beginning and end-of-day calibration injections of He/CH 4 and He/CO 2 (or the auto calibration check using the cmdAutoCalibCheck command); 3) full instrument calibration, performed every six mont hs, using KHP, sucrose, and the two calibration gases; and 4) temperature calibrations performe d every six months using temperature-sensitive indicating liquids with different melting points.

3.1.1 End-of-Run Calibrations (Description)

The end-of-run calibration consists of a set quantity of He/CH 4 calibration gas which is automatically injected by the carbon program. A ll FID readings during the analysis run are normalized to this peak to minimize the effect s of FID performance and electronic drift over time. The end-of-run calibration occurs automati cally at the end of each analysis run and requires no operator intervention. The integrated calibration peak counts should be checked by the operator immediately after each run to confirm that the analyzer is operating satisfactorily. Calibration peak area counts should be greater than 20,000 and within an acceptable range for the specific analyzer. Check daily records to compare and determine analyzer performance and stability.

3.1.2 Routine Calibrations (Description)

Routine calibrations must be performed at the beginning and end of each day, either manually or by using the automated routine calibration command ( cmdAutoCalibCheck ) in the CarbonNetWork database Command table.

3.1.2.1 Automated Routine Calibration (Description & Instructions)

The automated calibration uses th e Carle valve to inject the CH 4 standard once in a He-only atmosphere, once in a He/O 2 atmosphere, and finally, the normal calibration peak at the end of analysis. The three peaks should have similar ar eas if the catalysts are in good condition and the calibration factor holds (See Figure 3-1). Use the following steps to perform this automated calibration:

• From the DRICarb.exe Welcome screen, select “Analysis” from the “Main” submenu.

• Set Type to “Sample” and select cmdAutoCalibCheck from the drop-down menu in the “Command table” field.DRI STANDARD OPERATI NG PROCEDURE Page: 30 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 3-1. Calibration thermogram from the cmdAutoCalibCheck command of the DRI Model 2001 Thermal/Optical Carbon Analyzer.DRI STANDARD OPERATI NG PROCEDURE Page: 31 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• The project name should be “CALIB”, Ba tch # should be “MM” for the month, Subbatch # should be “DD” for the day, and th e Sample ID should be in the format “CxxYYYYMMDD” where “xx” is the anal yzer number (e.g. C0720050710 for analyzer number 7, run on July 10, 2005).

• Set the Run # (“1” for first calibration of the day and “2” for second calibration of the day, etc.). Enter “1” in the Punch area, a nd Deposit area fields. Click on “OK” and then click “Run”.

• Review the thermogram and record thes e values in the logbook and on the Daily Analyzer Checklist as shown in Figure 2-8. The three calibration peak counts (OC3, EC1, LtPyMid) should be above 20,000 and within the acceptable range for the specific analyzer, and should be almost identical in area (and within 10% of the “Calibration Peak Area” value show on the tabular printouts). Ch eck the average C value for the calibration gas against those posted on each carbon analyzer.

• Whenever the MnO 2 or Ni catalyst is replaced, an automated routine calibration should be run to confirm that the previous calibration curve holds.

3.1.2.2 Manual Routine Calibration (Instructions)

• From the DRICarb.exe Welcome screen, select “Analysis” from the “Main” submenu.

• Set Type to “Calib” and select cmdCalib-HeO 2 (for example) from the drop-down menu in the “Command table” field. The setup screen is shown in Figure 3-2.

• Project name, Batch #, and, Sub-batch # are not required or available fields for entry. The sample ID should be in the format “MIxxYYYYMMDD” for CH 4 injection or “CIxxYYYYMMDD” for CO 2 injection where xx is the analyzer number (e.g. MI0720050710 for a CH 4 injection on analyzer number 7, run on July 10, 2005).

• Set the Run # (“1” for first calibration of the day and “2” for second calibration of the day, etc.). Click on “OK” and then click “Run”.

• Select the atmosphere for calibration under the “Cal Gas” (either CH 4 or CO 2 ) menu and select the proper “Carrier Gas” (either HeO 2 or He; HeO 2 for beginning of day and HE only for end of day). These should be altern ated with the calibration gas. Verify the command table matches the options selected.DRI STANDARD OPERATI NG PROCEDURE Page: 32 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 3-2. Setup Screen for Manual Gas Calibration for the DRI Model 2001 Thermal/Optical Carbon Analysis Program.

• Choose “OK” to proceed with the analysis, or “Exit” to leave the program. The analysis will start with the following screen as show n in Figure 3-3. You will note that the top portion contains all the information in the analysis Setup screen. The bottom half will display the thermogram when the run is initiated.

• Start a run by clicking on “Run”. After the com puter states, “Please load gas syringe”, flush the gas syringe with the calibration gas at least three times and then load it with the calibration gas. The computer will then st ate, the “Time remaining until load - XX seconds” and then “Inject calibration gas”. Follow the verbal instructions to inject the calibration gas through the septum. Inject the gas through the septum. Hold the plunger down with needle still inside septum for 10 seconds, or until peak appears.

• Calibration gas injections should be in the following ranges for 1000 μl gas:

Manual Injection Lower Allowable Limit Upper Allowable Limit CH 4 20.36 μg carbon 1 * 22.50 μg carbon 1 *
CO 2 20.28 μg carbon 2 * 22.41 μg carbon 2 * Final Calibration Peak 20,000 --

1 Calculated in a real laboratory environment. For a 5.12% CH 4 standard at 646 mm Hg at 24 °C, actual mass of methane is 21.43 μg

carbon.

2 Calculated in a real laboratory environment. For a 5.10% CO 2 standard at 646 mm Hg at 24 °C, actual mass of carbon dioxide is

21.34 μg carbon. * Lower Allowable Limit equals to 5% lowe r than the actual mass; Upper Allowable Lim it equals to 5% higher than the actual mass

.

Limits should be adjusted according to the real laboratory environment.DRI STANDARD OPERATI NG PROCEDURE Page: 33 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 3-3. The Analysis Screen during Manual Gas Calibration for DRI Model 2001 Thermal/Optical Carbon Analysis Program.

• Note: Each time the MnO 2 or Ni catalyst is replaced, the instrument calibration should be checked to confirm that the previous calibration curve holds. A flow check and balance should always be performed after cat alyst changes. Additional checks can be done by running a comparison sample (if availa ble) or running two points from the six CH 4 /He calibration volumes and two points from the six CO 2 /He volumes used in the full calibration. The calibration peak area may al so need to be checked for significant changes that would require a full calibration to calculate a new slope.

3.1.3 Full Calibration (Description)

Full instrument calibration, performed semiannually or as needed, establishes the calibration slope used in converting counts to μg of carbon, as explained in the next section. Instrument calibration involves spiking pre-fired quartz punches with 5.0 to 20.0 μl of the 1800 ppm KHP and sucrose solutions and injecting 200 to 1000 μl of the CH 4 and CO 2 gases.

Four types of standards are used to ca librate the carbon analyzers: 5% nominal CH 4 in He, 5% nominal CO 2 in He, KHP, and sucrose. Only the calib ration gases are used on a daily basis as analyzer performance monitors. KHP and sucrose are used in conjunction with CH 4 and CO 2 semiannually to establish the calibration curve of each analyzer.DRI STANDARD OPERATI NG PROCEDURE Page: 34 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

3.1.3. 1 Preparation, Ranges and Traceability of Standards

The calibration is done by injection of a known vol ume of the standard to yield a calibration curve of peak area ratio of injected carbon: CH 4 (internal standard) versus μg C injected (Internal Standard Calibration Method). For the best accurac y, the temperature and pressure at the time of analysis need to be taken into account. For a 100% CH 4 or CO 2 standard at 760 mm Hg at 20 °C, each microliter = 0.499 μg carbon. For a 5% standa rd, it will be 0.02495 μg C/μl at standard temperature and pressure (STP; 20 ° C, 760 mm Hg). The Ideal Gas Law should be used to correct for the temperature and pressure of the laboratory.

12gas cal of % 0.08206 1 273.15) (T 1
760 Pa μLper C μg Acutal × × ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

+ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛

=

where Pa is pressure in mmHg, T is ambient temperature.

The calibration gases are traceable to NIST standards. The calibration gases are assayed for exact concentrations by the gas supplier; the assay value is obtained from the tag on the cylinders and is typically determined by GC.

To prepare an 1800 ppm standard, the KHP is dr ied at 110 °C for two hours before dispensing. Transfer 0.3826 g of KHP into a glass 100 ml volum etric flask after the KHP has come to room temperature inside a desiccator. The weight of KHP used must be recorded. Dilute to volume with 0.4 ml concentrated hydrochloric acid (H Cl) and 99.6 ml Nanopure water. Mix the KHP thoroughly. Store this solution in a refrigerator until it is used for calibration purposes. This solution is good for 40 days. Label the flask with the chemical name, the date of preparation, the name of the chemist preparing the solution, a nd the exact concentration. The concentration, nominally 1800 ppm carbon, is calculated by:

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ × ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

= KHP of MW 12 KHP in carbon of no ml in prep solutionof vol g in used KHP of weight mL per C μgActual

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ × ⎟ ⎠ ⎞ ⎜ ⎝ ⎛

= g μg 10
204.23 12 8
ml 100 gin used KHP ofweight

.. 6 ge

The nominal 1800 ppm standard, the sucrose so lution, is prepared by transferring 0.428 g of sucrose into a glass 100 ml volumetric flask. Dilute to volume with acidified Nanopure water (see blank solution preparation instructions be low). Mix the sucrose thoroughly. Store this solution in a refrigerator until it is used for calibration purposes. This solution is good for 40DRI STANDARD OPERATI NG PROCEDURE Page: 35 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
days. Label the flask with the chemical name, th e date of preparation, the name of the chemist preparing the solution, and the exact concentration. The concentration is calculated by:

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ × ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

= sucroseof MW 12 sucrosein carbon of no ml in prep solutionof vol g in used sucroseof weight mL per C μgActual

⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛ ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ × ⎟ ⎠ ⎞ ⎜ ⎝ ⎛

= g μg 10
342.31 12 12
ml 100 gin used sucrose ofweight

.. 6 ge

To prepare a blank solution, add 0.4 ml of concen trated HCl to a glass 100 ml volumetric flask and dilute to volume with Nanopure water. This acidified Nanopure water is made fresh each time a 1800 ppm KHP stock solution is prepared.

Only a limited set of primary standards (NIST- traceable) currently exist for carbon analysis. Ideally, such standards should include a range of organic compounds from low- to highmolecular weights and with varying degrees of susceptibility to pyrolysis, as well as EC and carbonate compounds. Currently, KHP, sucrose, a nd the two calibration gases are used at DRI for calibration and system audit purposes.

3.1.3.2 Calculating Calibration Slope

The calibration slopes derived from the two ga ses and the KHP- and sucrose-spiked filter punches are averaged together to yield a single ca libration slope for a given analyzer. This slope represents the response of the entire analyzer to generic carbon compounds and includes the efficiencies of the oxidation and methanator zones and the sensitivity of the FID. Note that the current calibration procedure is based only on TC, as no routine procedure exists to check the accuracy of the OC/EC split. An example of the spreadsheet is shown in Figure 3-4.

3.1.3.3 Typical Accuracy of Calibration Standards

The accuracy of the calibration standards is pr imarily limited by the accuracy of the calibration gas assays, the accuracy of the preparation of the KHP and sucrose solutions, and the technician’s injection technique. The calibra tion slopes determined by these four compounds historically differ by less than 5% on a given analyzer if sufficient care is taken during the calibration procedure (Section 3.1). Figure 3-5 shows an example of plotted calibration curves.DRI STANDARD OPERATI NG PROCEDURE Page: 36 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 3-4. Example of calibration summary worksheet used to determine calibration slope.

Calibration volume C in CH 4 / He Injection Calibration Injection / Standard Run # (μL) (μg) Peak Counts Peak Counts Calibration Slope

CH4 MI040106-1 200 4.18 4913 25194 0.1950 21.45 CH4 MI040106-2 500 10.46 12240 25095 0.4877 21.44 CH4 MI040106-3 700 14.64 17081 25502 0.6698 21.86 CH4 MI040106-4 1000 20.92 24094 25769 0.9350 22.37 CH4 MI040106-5 1000 20.92 24011 25846 0.9290 22.51 CO2 CI040106-1 200 4.13 4807 25738 0.1868 22.10 CO2 CI040106-2 500 10.32 12196 25901 0.4709 21.92 CO2 CI040106-3 700 14.45 17214 26114 0.6592 21.92 CO2 CI040106-4 1000 20.64 24425 26204 0.9321 22.14 CO2 CI040106-5 1000 20.64 24433 25969 0.9409 21.94 SUC SU20060401-5UL 5 9.01 12490 25952 0.4813 18.72 SUC SU20060401-10UL 10 18.02 22626 25987 0.8707 20.70 SUC SU20060401-15UL 15 27.03 32686 26140 1.2504 21.62 SUC SU20060401-15UL 15 27.03 35584 26336 1.3512 20.01 SUC SU20060401-20UL 20 36.04 44753 26087 1.7155 21.01 KHP KHP20060401-5UL 5 9.00 11546 26386 0.4376 20.56 KHP KHP20060401-10UL 10 17.99 23878 26608 0.8974 20.05 KHP KHP20060401-15UL 15 26.99 33340 26702 1.2486 21.62 KHP KHP20060401-15UL 15 26.99 33156 26530 1.2498 21.60 KHP KHP20060401-20UL 20 35.99 44472 26504 1.6779 21.45DRI STANDARD OPERATI NG PROCEDURE Page: 37 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 3-5. Example DRI Carbon Analyzer Calibration Curves.

CA#7 Calibration

y = 21.055x

0 5 10 15 20 25 30 35 40

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 Peak Area/Calibration Peak Area (no units)Calculated Carbon (ug)DRI STANDARD OPERATI NG PROCEDURE Page: 38 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

3.1.3.4 Data Treatment for Calibration Data

• Calibration values are plotted as ratio of the integrated sample peak counts to the calibration peak counts vs. the actual calcu lated μg carbon (Figure 3-5). Obvious outliers are identified and rerun. Linear regression is performed on each set of calibration data (separate calculations for KHP, sucrose, CH 4 /He, and CO 2 /He). The slope (m) is calculated from: 

## ( ) 

# ( ) ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

= 

## ∑ ∑

2
i ii

x xy m

The standard deviation (s) is calculated by:



## ( )



# ∑ ∑

−

− = 2 2

1 1

i ii

x mxy

n σ

where:


## ( ) ( ) x injected carbon peak area calibration peak area i =

and : 

## ( ) y calculated carbon in spiked filter or manual injection g

i = μ

• Note that this is a special form of the re gression formula which ensures that the curve passes through the origin.

• The resulting slope is compared to previous calibration results. New values should be no more than 10% different than previous calibrations if no major analyzer changes have been made. If variation is > 10%, calibration must be redone to verify values.

• The new slope for each analyzer (derived from combined CH 4 , KHP, and sucrose data) is placed into the Carbon.par file for each analyzer; this file contains analyzer parameters which are read into the Carbon pr ogram when it is first started. Therefore the Carbon.par file must be edited while the progr am is closed and the parametersDRI STANDARD OPERATI NG PROCEDURE Page: 39 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
will take affect when the program is restarted. The date and version number in the Carbon.par file is also updated.

• Calibration data and plots are retained electroni cally and in file fold ers stored with the raw analysis data.

3.1.3.5 Calculations

The conversion of integrated peak counts to μg of carbon for each peak in the thermogram is performed by the computer at the end of the analysis program. For reference purposes, the calculation is:

)counts n ncalibratio internal( ) slopencalibratio(x)baseline above counts peak integrated( C/punch g peak = μ

For IMPROVE_A thermal protocol, the peaks re ported are: four organic peaks (OC1, OC2, OC3, and OC4) corresponding to 140, 280, 480, and 580 °C in He atmosphere, respectively; three elemental carbon peaks (EC1, EC2, and EC3) corresponding to 580 °C after the introduction of O 2 , 740, and 840 °C, respectively; and three pyrolyzed organic carbon peaks (Lower, Regular, and Upper Sp lits) by reflectance and transmittance, corresponding to the peaks after the introduction of O 2 and before the Lower Split Time, Regular Split Time, and the Upper Split Time, respectively, for the reflectance and transmittance optical charring correction (see S ection 1.7 and Figure 4-4). The EC reported includes pyrolyzed carbon.

Carbon values per punch are converted to μg C/cm 2 by:


## ( ) ( ) areapunch

punchCg cmCg 2 μ =μ

Finally, carbon values are converted to μg C/filter by: 

# ( ) ( ) areadepositfiltercmCgfilterCg 2 μ=μ

3.2 Instrument Calibration Instructions

3.2.1 Full Gas Calibration

• To perform the full calibration, select “A nalysis” from the Main menu of the DRICarb.exe program Welcome screen.DRI STANDARD OPERATI NG PROCEDURE Page: 40 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Choose “Calib” under the “Type” drop down menu. Project name, Batch #, and, Sub-batch # are not required. In th e “Command table drop-down”, select cmdCalibHe (for example). Fill out the Sample ID, Run #, and Tech Initials fields. The sample ID should be in the format, “MIxxYYYYMMDD_zzzz” (where “MI” is for CH 4 injection; use “CI” for CO 2 injection; xx is for the analyzer number and zzzz is the volume of gas injected). You can also select FID ID (typically FID_8) to determine the FID peak area and make comments and flag the analysis from this screen before the analysis starts.

• Select the atmosphere for calibration unde r the “Cal Gas” menu and select the proper “Carrier Gas”. (He-only gas is recommended when doing full gas calibrations.) Verify the command table matches the options selected.

• Enter the technician initials in the “Tech initials” field.

• Choose “OK” to run the analysis, or “Exit” to leave the program. The analysis will start with the screen as shown in Fi gure 3-2. You will note that the top portion contains all the information in the Setup screen. The bottom half will display the thermogram when the run is initiated.

• Start a run by clicking on the Run comma nd button. After the computer states “Please load gas syringe” flush the gas syri nge with the calibration gas at least three times and then load it with the calibrati on gas. Time remaining until load will be stated, and then “Inject calibration gas”. In ject the gas through the septum. Hold the plunger down with needle still inside septum for 10 seconds, or until peak appears.

• The CO 2 and CH 4 calibrations are run using the “Calibration” options from the main menu. The following volumes are injected:

– 200 μl CO 2 gas (use 1000 μl syringe)

– 500 μl CO 2 gas (use 1000 μl syringe)

– 700 μl CO 2 gas (use 1000 μl syringe)

– 1000 μl CO 2 gas (do once with 1000 μl syringe and once with 2500 μl

– syringe)

– Repeat for CH 4

• Record these calibration values in the logbook as in Figure 2-6.

• The integrated peak counts are extracted manually from the tabular printouts and entered into the spreadsheet which is used to determine the final calibration.DRI STANDARD OPERATI NG PROCEDURE Page: 41 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

3.2. 2 Full Sucrose and KHP Calibrations

• To perform the full calibration, select “A nalysis” from the Main menu of the DRICarb.exe program Welcome screen.

• Choose “Sample” under the “Type” drop down menu. Complete the information about the sample, including: Project Name , Batch #, and Sub-batch #. The Project name should be “SUKHPCAL”, the Batch # s hould be “MM” for the month; and the Sub-batch # should be “DD” for the date.

• A clean blank quartz punch is baked in the analyzer oven at 900 ° C for 10 minutes using cmdBakeOven from the Command table.

• After baking the quartz punch, change to cmdImproveA under Command table.

• Perform system blank before running KHP or sucrose.

• Enter the Sample ID number or place your mouse cursor in the field. The sample ID should be in the format, “SUxxYYYYmmdd_zz” (where “SU” is for sucrose spiking; use “KHP” for KHP spiking; xx is the analyzer number and zz is the volume [05, 10, 15, or 20 μl]). You can also select FID ID (typically FID_8) to determine the FID peak area and make comments and flag the analysis from this screen before the analysis starts.

• Enter the Run #; the Punch area and Deposit area should be “1” for the filter being analyzed.

• Enter technician initials in the “Tech initials” field.

• After the punch has cooled to less than 50 ° C, the KHP or sucrose solution (prepared as described in Section 3.1.3.1 and kept at room temperature) is injected onto the punch using a 25 μl syringe. The following volumes are used:

– 5 μl KHP and sucrose solution

– 10 μl KHP and sucrose solution

– 15 μl KHP and sucrose solution (do twice)

– 20 μl KHP and sucrose solution

– no injection (as a system blank; see Section 4.1.5.1)DRI STANDARD OPERATI NG PROCEDURE Page: 42 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

– 20 μl acidified Nanopure water only (c heck of background level of Nanopure water)

• Flush the syringe at least three times with the calibration solution before taking up the volume for injection. Pump the syringe plunger to remove any trapped bubbles.

• Slowly spike the solution in the center of quartz punch and wash the syringe with Nanopure after use. If the solution is spiked too quickly it will bead up and run off the punch.

• Click “OK” on the analysis “Setup” scr een. The boat will load to the calibration position.

• The computer will ask, “Would you like to proceed or would you like to delay analysis?” Enter the length of time in sec onds you wish to delay the beginning of the analysis in the Delay box. This is used to purge dry a filter disc that has been deposited with an aliquot of KHP or sucrose standard solution, or when the sample is acidified for carbonate removal. In general, allow ~1 minute of purge time for every μl of solution deposited (e.g., 5 μl=300s, 10μl=600s, 15μl=900s and 20μl=1200s). Click “OK” and analysis will begin.

• Allow the punch to dry thoroughly; the punch w ill turn from translucent to opaque as it dries. The punch must be dry to avoid wa ter vapor effects on the FID and the laser reflectance and transmittance signals. Select the cmdImproveA option from the analysis menu to start.

• The integrated peak counts for all seven temperature fractions for the sample and calibration peaks are recorded. The total p eak is calculated by adding the peak area from OC1, OC2, OC3, and OC4, as well as EC1, EC2, and EC3. Pyrolysis counts are not included in the total.

3.2.3 Temperature Calibrations

Temperature calibrations are performed semiannually on all instruments to verify that the sample temperature is as accurate as possible.

3.2.3.1 Temperature Indicators

Since it is not possible to sense the temperature of the sample directly, materials were sought that: 1) could be placed where the sample would normally be located, and 2) would cause sharp reactions when known temperatures were achieve d. Quick-drying temperature-indicating liquids of different melting points, Tempilaqo G (Tempil, Inc., South Plainfield, NJ, USA), were used as temperature indicators in muffle furnaces. A Te mpilaqo G set contains long-chain hydrocarbons suspended in an organic solvent, which change their appearance at 44 specific temperaturesDRI STANDARD OPERATI NG PROCEDURE Page: 43 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
spanning 80-1000 ° C. The accuracy of Tempilaq ° G is certified within ± 1% of its designated temperature and is traceable to the National Institute of Standards and Technology (NIST). Tempilaqo G is bottled in liquid form and dries qui ckly to a dull, opaque film when applied to a surface. As the surface is heated to the desi gnated temperature, the film liquefies and is accompanied by a change of appearance that can be optically monitored to determine sample temperature.

3.2.3.2 Analyzer Preparation

Preparation of the Model 2001 analyzer for temperature calibration includes the following:

• Change par file to 1 and 0 for slope inte rcept (par file must be edited with the program closed).

• Disconnect the back valve to prevent contaminating the system

• Replace existing MnO 2 oven with a clean backup ove n (without a catalyst) to prevent contamination of the main oven. Install without connecting to the back valve.

• Connect an Erlenmeyer flask with ice in it where the oven connects to the back valve. This will help condense the organics when the Tempilaq is heated up.

3.2.3.3 Standard Preparation

Temperature calibration requires two pre-fire d quartz-fiber filter (#2500 QAT-UP, Pall Life Sciences, Ann Arbor, MI) punches (0.5 cm 2 for DRI analyzer) and a clean matching-sized quartz disk (Continental Glass Engineering, Burbank, CA). Quartz-fiber filter punches are sliced in half (horizontally) with a filter-slicing device (Fung et al., 2004). A thin layer of Tempilaqo G (~25 μL) is uniformly applied to the glass and/ or quartz disk surface with a 0.1 ml Eppendorf graduated Combitip (Brinkman Instruments Inc., Westbury, NY), and, before drying, is immediately covered with a sliced filter punch. For cost savings, a glass, instead of quartz, disk can prepared by a technician in the lab from a glass slide cover and used for Temiplaqo G at temperatures > 520 ° C. Higher temperatures require the quartz disc to prevent melting. The disc sandwich (i.e., temperature standard) is then loaded on a sample holder for analysis. The mass of applied Tempilaqo G is determined gravimetrically to ensure its mass is ~10%.

3.2.3.4 Temperature Program

After insertion of the temperature standard into the analyzer, the temperature is slowly (2 °C/min) ramped across a 50 °C range containing the specified Tempilaq° G melting point. This slow ramping creates a quasi-equilibrium condition that allows the phase transition point to beDRI STANDARD OPERATI NG PROCEDURE Page: 44 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
resolved. Temperature indicators 121 through 510 are replicated three times and 704 and 816 are replicated twice. When the specified te mperature is reached, the Tempilaqo G liquefies, causing a detectable change in reflectance and transmittance.

Figure 3-6 demonstrates the thermocouple temperature, reflectance, and transmittance as a function of thermal analysis time. In the example provided, the reflectance and transmittance remained relatively flat until the temperature a pproaches its specified value of 184 °C. Figure 3- 7 compares the time series of reflectance, tran smittance, and their respective first- and secondorder derivatives. The second-order derivative (change in the slope) recorded the inflection point of reflectance or transmittance that provided th e best indication of the attainment of the designated temperature. Thermocouple temperatur e at this critical point was recorded as “measured” temperature. The temperature deviation ( Δ T) between the sample and the thermocouple temperatures is determined by comp aring the rated Tempilaqo G temperature with this measured value (Chow et al., 2005).

In the Model 2001, the reflectance-based method generally gave a lower liquefying temperature than the transmittance-based method, within ±2 oC. Given the uncertainty in the Tempilaqo G temperature rating of ± 1%, calibrations based on the two optical methods were considered to be equivalent; therefore, their means were use d. Among temperature indicators that achieve an adequate signal/noise ratio, temperat ure indicators of 121, 184, 253, 510, 704, and 816 ° C were chosen for IMPROVE_A protocol temperature calibration (Chow et al., 2005, 2007). Note, the 510 ° C temperature experiences charring and therefore, transmittance results are variable.DRI STANDARD OPERATI NG PROCEDURE Page: 45 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 3-6. Temperature ramping with a Temp ilaqo G temperature indicator rated at 184

° C. Also shown are reflectance and transm ittance of the temperature indicator (if available). The vertical dashed line indicates the achievement of the rated temperature.

0 400 800 1200 1600 2000 2400 2800

0 200 400 600 800 1000 1200 1400 1600 1800 2000 Time (sec) 0 50 100 150 200 250

Transm ittance Reflectance Tem peratureLaser Reflectance/Transmittance (mV) Transm ittance

Reflectance Tem peratureThermocouple Temperature (°C) Transmittance

Temperature

ReflectanceLaser Reflectance/Transmittance (mV)

Time (sec)DRI STANDARD OPERATI NG PROCEDURE Page: 46 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 3-7. Reflectance and transmittance me asurements and their first and second derivatives over time with a Tempilaqo G temperature indicator rated at 184 ° C (Figure 3- 6). The vertical dashed line indicates the ac hievement of the rated target temperature.

0 400 800 1200 1600 2000 2400 2800

0 200 400 600 800 1000 1200 1400 1600 1800 2000 Time (sec) -35 -25 -15 -5 5 15 25 35First/Second DerivativeLaser Reflectance/Transmittance (mV)

(Tempilaq’s melting point 184 ± 2 oC) Transmittance Reflectance

1 st Reflectance Derivative

1 st Transmittance Derivative

2 nd Reflectance Derivative 2 nd Transmittance DerivativeDRI STANDARD OPERATI NG PROCEDURE Page: 47 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 4 PROCEDURES

4.1 Detailed Procedures

4.1.1 Analyzer Start-Up

When the analyzer is started up for the first tim e, or after an extended period of non-operation, it will take a period of conditioning to reach a stable system background. At start-up, allow all the gases to purge through the system for ~30 minutes before heating the various zones in a stepwise manner. Allow the FID and Line Heaters to r each operating temperatures of 120 °C and 105 °C, respectively, before heating up the oxygenator and me thanator. Heat both catalysts at 120 °C for about half an hour, then in ~100 °C increm ents with ~30 min. hold time until the final temperatures of 912 °C and 420 °C are reached for the oxygenator and methanator, respectively.

The following steps outline analyzer start-up:

• Check all gas cylinder pressures; cylinders with gas pressures less than 500 psi should be replaced before beginning the day's analysis.

• Check that all gas delivery pressures are correct:

Hydrogen (H 2 ) 15 psi

Helium(He) 15-40 psi (check label on regulator for current setting)

Compressed air 15 psi for FID, 25 psi for breech actuation

O 2 /He mix 15 psi

CH 4 /He mix 10 psi

CO 2 /He mix 10 psi

• Check that the FID is lit by holding a pair of tweezers over the FID exhaust stack and watching for condensation. If the FID is not lit (as immediately after the H 2 or compressed air cylinders are changed), relight the flame by turning the H 2 rotameter to the upper limit (as posted on the flow meter) and holding a butane lighter or match over the FID stack. A soft pop indicat es that the flame has been lighted. Verify that the flame remains lit by the tweezers test. Often the flame will not stay lit the first try, especiallyDRI STANDARD OPERATI NG PROCEDURE Page: 48 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

after the H 2 cylinder is changed and air gets into the gas lines. Return the rotameter to the operation setting after the flame is lit.

• Check and readjust, if necessary, all gas flow s at the analyzer. The correct readings are posted on each rotameter. Read through the cente r of the ball. If dr astic adjustments are required on one analyzer, recheck that flow s on the other analyzers have not been affected.

• Turn on the computer monitor. Note: the com puters are generally left on at all times; only the monitors are turned off when the analyzers are not in use.

• Confirm that the date and time on the computer are correct.

• Wipe the sample tweezers, flat glass plat e, and punching tool with clean KIMTECH wipe, taking care not to contact the cleaned su rfaces with fingers or other dirty items. Check to make sure that no fibers from the KIMTECH wipe are left on the surfaces.

• Begin the daily entry in the Carbon Analy zer Logbook. Entries should follow the format in Figure 2-6.

• Make sure that the printer has enough paper for the day and that the toner cartridge is producing legible text and graphics.

• Go to C:\CarbonNet, then double click the DRICarb.exe program icon to begin the carbon program (or double click the DRICarb.exe shortcut on the computer desktop). The DRI welcome screen appears as depicted in Fi gure 4-1. Verify that the correct version of the software and database are being used. For normal analysis, the database should be

“ CarbonNetWorkXX.mdb ”, where XX is the analyzer number.

If for some reason the program freezes, allo w the sample oven to cool to below 200 ° C and then close the program and restart DRICarb.exe

.
4.1.2 Leak Checks

Perform leak checks daily to detect leakage in the sample oven.

4.1.2.1 Manual Leak Check

• With the breech closed, flip the oven outlet t oggle on the side of the analyzer down (off) and let the sample oven pressure reach ~3 ps i. Most systems are working in the ~2-2.5 psi range, but a leak is easier to detect when th e pressure is at ~3 psi. Close the oven inlet toggle, on the front of the analyzer, and watch for a decline in the sample oven pressure.DRI STANDARD OPERATI NG PROCEDURE Page: 49 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 4-1. DRI Welcome Screen.

NOTE: When using the carbon analysis software, clicki ng on the Exit button closes the program. Exiting in the midst of an analysis is not advisable, as the analy zer will revert to the default settings (see settings under Options\Manual); in such a case, a hot thermoc ouple will retract, possibly damaging the Teflon seal.
A “leak free” condition is indicated by a steady pressure reading, or a decline of 0.01 psi or less per second (~0.01 ml/sec).

• If the pressure is stable, f lip the outlet oven toggle and then the inlet oven toggle back to the on position (up). This is to avoid pressuri zing the oven if the inlet toggle is flipped first.

• If the pressure is not stable, use a He leak detector (Alltech, Deerfield, IL) to locate the leak. Check the following items and correct accordingly:

– All ferrules (especially the reducing ferrule), fittings and seals.

– Quartz oven.

– All tubing.

– Thermocouple.DRI STANDARD OPERATI NG PROCEDURE Page: 50 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

– Breech O-ring.

• If the system still leaks, wipe all threads and ferrules with a dry KIMTECH wipe, reassemble, and retry.

• Also, check the breech O-ring to en sure that it sits squarely in the groove and that there is sufficient pressure to close the breech.

• Refer to the carbon analyzer’s Troubleshooting Manual for additional tips and procedures.

Once the system passes the leak test, make sure that the analyzer’s multi-function switch (at the left of the front panel) is set at Auto in order to continue with routine an alysis. Allow the system pressure to return to its original value and r ecord this value on the Daily Analyzer Checklist shown in Figure 2-8. The pressure should be consistent with previous day’s values.

4.1.3 Oven Bake

A daily oven bake is performed to ensure the system is clean before beginning analysis. The oven bake can be performed manually or by using an automated command from the command table.

4.1.3.1 Manual Oven Bake

Use the following procedure to perform a manual oven bake:

• Select “Manual” from the “Main” submenu. Fr om the “Manual” screen, select “Control” on the drop-down menu list. (Note: analyzer must be in “Auto” mode for the manual control to work.) This will bring up th e “Control” screen. Change the “Oven Temperature” field to “1000”. Change the “Sam ple Position” field to “Analyze”. Click “Go”. This will heat the oven to approximately 950 ° C, depending on the instrument’s calibration. Exercise caution when working around hot surfaces of the analyzer.

• Repeat until the system is clean. Sample runs or calibrations may then begin.

• System blanks (section 4.1.5.1) are run after the oven bake.

• Stop bake after 15 minutes; set temperature to 5 ° C

4.1.3.2 Automatic Oven Bake

Use the following procedures to perform an automatic oven bake:DRI STANDARD OPERATI NG PROCEDURE Page: 51 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• From the main welcome screen, select “Analysis”.

• Set Type to “Sample” and select cmdBakeOven from the drop-down menu in the “Command table” field.

• Use Project Name “SYSBLK”, Batch # “MM” for the month and Sub-batch # “DD” for the day.

• The Sample ID should be in the format “BxxYYYYMMDD” where “xx” is the analyzer number and YYYY is the year (e.g. B0720050715 for analyzer number 7 on July 15, 2005,).

• Set the Run #, Punch area, and Deposit area fields to “1”. Click “OK”, then “Run”.

• Repeat until the system is clean. Sample runs or calibrations may then begin.

• System blanks (Section 4.1.5.1) are run after the autocalibration (Section 3.1.2.1) has been completed and shows an acceptable range.

• The following items should be checked and r ecorded on the Daily Analyzer Checklist shown in Figure 2-8. These values can be obtained by choosing the manual option from the main welcome screen.

– Reflectance and transmittance (must be measured with a clean blank filter in the “analyze” position).

• Reflectance range should be between 1400 and 2000 and consistent with previous days’ values.

• Transmittance range should be between 800 and 1300 and consistent with previous days’ values.

– System blank values

• Total carbon must be less than 0.2 ug/cm 2

– Calibration values

• Specific to analyzer and must be consistent with previous days’ values.DRI STANDARD OPERATI NG PROCEDURE Page: 52 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

4.1. 4 OC/EC Analysis

Based on the analysis list for the day, retrieve the samples to be analyzed from the sample freezer and place in a Styrofoam cooler with blue i ce, or in the analysis room refrigerator.

Routine analysis procedure assumes carbonate will not be measured. For carbonate analysis, refer to Section 4.1.5.2, “Carbonate Analysis”.

Always execute the cmdBakeOven command to bake the oven before beginning analysis each day (refer to section 4.1.3). This will ensu re the system is clean (< 0.2 μg TC/cm 2 ). Run a system blank with the IMPROVE_A protocol.

4.1.4.1 Analysis Preparation

• Verify the computer date and time is correct.

• Verify sample oven pressure reading and speci fied flow ranges in the front-panel flow
meters.

• Wipe the flat glass plate, tweezers, and punching tool thoroughly with a dry KIMTECH wipe.

• Based on the analysis list, remove the sample to be analyzed from the Styrofoam cooler or refrigerator.

• Record the filter ID in the analyzer log book (Figure 2-6).

• Open DRICarb.exe from the c:\CarbonNet folder or use the desktop “shortcut” to DRICarb.exe . Verify correct software version number on the Welcome screen.

• Select “Analysis” from the “Main” submenu of the Welcome form. This will initiate the analysis protocol, as shown in Figure 4- 2a and 4-2b. You can also select FID ID (typically FID_8) to determine the FID peak sensitivity.

• In the analysis “Setup” form, enter “Sample” for the Type.

• Polarity should default to “Unipolar”.

• Fill out the information about the sample, including: Project Name, Batch #, and Subbatch #.

• Under “Command table” select cmdImproveA

.DRI STANDARD OPERATI NG PROCEDURE Page: 53 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Enter the Sample ID number, or place your mouse cursor in the field and use a barcode scanner to read the barcode on the Petri dish.

• Enter the Run #, Punch area and Deposit area for the filter being analyzed.

• Enter technician initials in the “Tech initials” field.

• Select any pre-analysis flags from the dr op-down menu in the “Flags” field. A list of valid choices is presented on the screen.

• Visually examine the filter and note any non-uniformity or unusual deposit. Remove it from the Petri slide or Petri dish with tw eezers, handling the filter only by the edge. Place the filter on the flat glass plate and rem ove a sample punch by pushing down gently on the punching tool. Rocking the punching tool slightly will ensure that the punch is completely severed. Try to remove the punc h from the edge of the deposit to avoid wasting the filter, while trying to avoid areas of non-uniform deposits.

• Leaving the sample punch in the punching tool, place the punching tool on a clean KIMTECH wipe. Return the filter to the Petri slide or dish, being careful to handle only the filter with the tweezers.

• If this is the first run of the day, or if th e analyzer has been cooled down, the analyzer will verbally prompt you to load the punch (“Pl ease load filter analysis”). If the analyzer was previously used, it will cool to 100 °C, then pull the boat back to the calibration position, continue cooling to 50 °C, and pull the boat back to the load position for the next analysis.

4.1.4.2 Loading the Filter Punch

• Use tweezers to remove punch from punch tool and place in analyzer boat.

• Click “OK” on the analysis “Setup” screen. The boat will load to the calibration position and the computer will ask, “Would you like to proceed or would you like to delay analysis?” Enter any appropriate flags and click “Commit”. Check to make sure a 90- second delay is in the “delay” box. Click “OK” and analysis will begin.

• Wipe the tweezers, flat glass plate, and punching tool with a clean KIMTECH wipe.

4.1.4.3 Post-Analysis

At the end of each analysis, data is saved to the database, split times are calculated, carbon peaks are integrated, and tabular and graphical printout s are produced. The sample boat will retract toDRI STANDARD OPERATI NG PROCEDURE Page: 54 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
the calibration position when it is sufficiently cooled by the fan (to < 100 ° C) and will continue to cool until it reaches less than 50 ° C.

• Examine the tabular printout (Figure 4-3) to confirm that the calibration peak counts are within specifications (typically >20,000 count s and within acceptable range for specific analyzer, see Section 3.1).

Figure 4-2a. Setup Screen for the DRI Mo del 2001 Thermal/Optical Carbon Analysis Program.DRI STANDARD OPERATI NG PROCEDURE Page: 55 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 4-2b. The Analysis Screen during Sample Analysis for DRI Model 2001 Thermal/Optical Carbon Analysis Program.DRI STANDARD OPERATI NG PROCEDURE Page: 56 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 4-3. Tabular Printout from DRI Model 2001 Thermal/Optical Carbon Analysis Program.DRI STANDARD OPERATI NG PROCEDURE Page: 57 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 4-3, continued.DRI STANDARD OPERATI NG PROCEDURE Page: 58 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Examine the thermogram (Figure 4-4) for proper laser response, temperature profiles, realistic carbon peaks, and the presence of the calibration peak at the end of the analysis.

• Examine the laser signal at the end of the run.

• If a problem is found, register it in the analyzer log book and run list, and notify the lab supervisor immediately.

• Add any appropriate analysis flags to the post-analysis form that appears at the end of the

run.

• Mark the analysis date on the sample analysis run list.

• Using clean tweezers, remove the punch from th e boat and tape it to the thermogram with transparent tape, ensuring that the punch is deposit-side up.

Repeat the above steps for additional analysis runs.

4.1.5 Special Analyses

4.1.5.1 System Blanks

System blanks are run at the beginning of each day. Follow the steps outlined in Section 4.1.3 on oven baking with the following exceptions:

• Follow the routine analysis procedure (S ection 4.1.4), but when prompted to load filter punch, remove the filter from the prev ious day and leave the boat empty for the analysis.

• Use Project Name “SYSBLK”, Batch # “MM” for the month, and Sub-batch # “DD” for the day. Punch area and Deposit area should be “1”.

• Use a Sample ID number “SBYYYYMMDD” de rived from the current date, where YYYY is the year (e.g. SB20050718 for July 18, 2005,).

• Calculated carbon concentrations should not be more than 0.2 μg carbon. Values greater than this warrant additional system blanks. Samples may not be analyzed until the system blank is <0.2 μg carbon.DRI STANDARD OPERATI NG PROCEDURE Page: 59 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Figure 4-4. Graphical output (thermogra m) from the DRI Model 2001 Thermal/Optical Analysis Program.DRI STANDARD OPERATI NG PROCEDURE Page: 60 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

4.1.5.2 Carbonate Analysis

• Enter the Sample ID, Run #, Punch area, and Deposit area. Select cmdImproveA_Carbonate from the “Command table” drop-down field and start the analysis program.

• Follow the steps under Section 4.1.3 until the sa mple punch is loaded into the boat. Load sample and click “OK”. When asked if you want to delay or continue analysis, click “OK”. After 90 seconds the punch auto matically centers under the acid injection port. The computer will prompt you to inject the hydrochloric acid (HCl), and then will state “Load syringe” and “XX seconds to acid injection”.

• Prior to acidification (approximately 90 sec onds elapsed analysis time), flush the 25 μl syringe with 0.4 M HCl into a waste beaker.

• Inject 20 μl of 0.4 M HCl th rough the septum port to the sample, ensuring that the needle bevel is turned toward the punch and that the needle tip is touching the top of the punch.

• When the analysis is underway, flush th e syringe with Nanopure water to prevent corrosion of the syringe plunger.

• After analysis, the program will delay any further analysis for 900 seconds to allow the punch to dry.

• After the carbonate analysis is completed, a tabular summary and a copy of the graph will be printed (similar in format to Figures 4-3 and 4-4). Select cmdImproveA from the “Command table” drop-down field and c lick “OK”. Click “Run” on the analysis Setup screen. The program will automatically cycle into the normal OC/EC analysis, using the same Sample ID. Heat from the oxidation oven will dry the sample in this position (for approximately 15 minutes) w ithout prematurely baking carbon from the sample; the sample temperature should not exceed 42 °C. When the punch is dry proceed with normal OC/EC analysis.

4.1.6 Analyzer Shut-Down

After the final sample for the day is analy zed, shut down the analyzers using the following procedures:

• Leave the last analyzed punch in the boat with the boat positioned in the Calibrate position. This punch will be used as the system blank the following morning and then taped to the corresponding thermogram.DRI STANDARD OPERATI NG PROCEDURE Page: 61 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Perform end-of-the-day calibration gas injection routine, or use cmdAutoCalibCheck command, and record the calibration peak c ounts. Any values outside the expected ranges should be investigated and rerun. Because low values from the end-of-day calibration could potentially invalidate the entire day's runs, any deviation from the accepted ranges must be noted and the cause identified. Notify the lab supervisor.

• Leave the DRICarb.exe software open.

• If desired, He-1, Cal Gas, He -2, and Air may be turned off with the toggle valves to conserve gases. However, all other gases should be left on as long as the oxygenator and methanator are heated.

• Place all of the day’s printouts, including calib ration data in a file folder labeled with the date and analyzer number. Place on th e lab supervisor's desk for Level I validation (Section 6.4).

• Leave the computers and analyzers on ove rnight unless the potential for power outages or surges exists. Turn off the monitors overnight.

• Make a final check of the gas cylinder pressu res to ensure that gas flow, especially the compressed air, will continue until so meone will be available to check them again.

• Move the samples and blue ice in the Styrof oam cooler or refrigerator back into the sample storage freezer and verify that the freezer is completely closed.

• If the 25 or 50 μl syringe was used fo r carbonate analysis, thoroughly rinse the syringe with distilled water and tightly cap all solutions. Store solutions in the refrigerator. Freezer storage may cause crystallization.

• Lock the carbon analysis room.

4.2 Abbreviated Procedures

4.2.1 Analyzer Start-Up

• Check pressures and delivery pressures in all gas cylinders.

• Check that all FIDs are lit by holding a pair of tweezers over the FID exhaust stack and watching for condensation. Relight if necessary.

• Check all gas flows at the analyzer; readjust if necessary.DRI STANDARD OPERATI NG PROCEDURE Page: 62 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Turn on the computer monitor.

• Confirm that the date and time on the computer are correct.

• Execute the DRICarb.exe either from the shortcut on the computer desktop or from C:\CarbonNet\.

• Confirm that the printers have enough paper fo r the day and that the toner cartridge is producing legible text and graphics.

• Wipe the sample tweezers, flat glass plat e, and punching tool with a clean KIMTECH wipe.

• Begin the daily entry in the Carbon Analyzer Logbook.

• Bake the oven for 10 minutes, or bake during leak test.

• Perform a leak test, involving isolating the oven and operating the Carle valve.

• Execute the cmdAutoCalibCheck command to verify the analyzer’s performance.

• Retrieve the samples to be analyzed from the sample freezer and place in the styrafoam cooler or refrigerator.

• Complete Daily Analyzer Check Sheet posted on each analyzer.

4.2.2 Leak Checks and Oven Baking

• Use manual option to set temperature to 900 ° C and let analyzer reach this temperature.

• With breech closed, flip oven outlet toggl e to the off position and let sample oven pressure reach ~3 psi.

• Flip the oven inlet toggle to the off position and watch for a decline in the sample oven pressure. If system is leak free, the pressure will remain stable.

• If the system is not stable, use a He leak detector to locate the leak; disassemble and reassemble the port fitting if necessary a nd check the O-ring for correct placement and
pressure.

• When system is stable, flip both the inlet and outlet oven toggles back to the on position.DRI STANDARD OPERATI NG PROCEDURE Page: 63 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• An oven bake can also be executed without a leak check by selecting cmdBakeOven from the drop-down menu in the “Command table”.

• Update the Daily Analyzer Checklist and verify values are within expected range.

4.2.3 OC/EC Analysis

4.2.3.1 Analysis Preparation

• Clean the tweezers, flat glass plate, and punching tool with dry KIMTECH wipe.

• Based on the analysis list, remove the sample to be analyzed from the Styrofoam cooler or refrigerator. Verify the sample ID against the analysis list.

• Remove a sample punch from the filter.

• Record the Sample ID in the analy zer logbook, along with any comments on the condition of the deposit or any other conditions which might affect analysis results.

4.2.3.2 Loading the Filter Punch

• Begin the analysis by clicking on “Analysi s” in the Welcome window and inputting the Project Name, Batch #, and Sub-batch #, verify the Command table is correct and enter the Sample ID, Run #, Punch area, Deposit area and Tech Initials.

• Enter Flags if appropriate (e.g., b1, i4, etc.)

• After the boat has cooled to 50 C or less, remove the previously analyzed sample punch and load the current sample punch.

• Clean the tweezers, flat glass plate, a nd punching tool with a dry KIMTECH wipe.

• Replace the Petri slide or Petri dish containi ng the filter into the Styrofoam cooler or refrigerator.

• Upon analysis completion, use a small piece of transparent tape to attach the sample punch to its thermogram, ensuring that the deposit side is facing up.

• At the end of the analysis, the push rod will automatically be pulled back to the Calibrate position to begin cooling.DRI STANDARD OPERATI NG PROCEDURE Page: 64 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

4.2.3. 3 Post Analysis

• Examine the thermogram for proper laser response, temperature profiles, realistic carbon peaks, and the presence of the calibra tion peak at the end of the analysis. Examine the tabular printout to confirm th at the calibration peak counts are within specifications (see Section 3.1). Finally, examin e the laser signal at the end of the run. Indicate successful analyses on the sample analysis list by recording the date. Notify the lab supervisor of any problems and r ecord them in the log book and on the run list.

• Repeat the above steps for additional samples.

4.2.4 Special Analyses

4.2.4.1 System Blanks

• Go through all the steps for a normal analys is, but do not remove the punch from the previous analysis. Proceed with the routine analysis.

• Use project name “SYSBLK”, Batch # “MM” for the month and Sub-batch # “DD” for the day. Punch area and Deposit area should be “1”.

• Calculated carbon concentrations from the system blank should not be more 0.2 μg carbon. Values greater than this warrant an additional system blank or oven bake.

4.2.4.2 Carbonate Analysis

• Follow the steps under Routine OC/EC Analysis until the sample punch is loaded into the boat.

• Enter the Sample ID, Run #, Punch area, and Filter area.

• When prompted for injection, spike 20 μl 0.4 M HCl onto the filter punch.

• Flush the syringe with Nanopure water between samples.

• Continue the normal OC/EC analysis wh en the carbonate cycle is complete, following the 20 minute delay allowed for drying.DRI STANDARD OPERATI NG PROCEDURE Page: 65 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

4.2. 5 Analyzer Shut-Down:

• Leave the last analyzed punch in the boat with the boat positioned in the Calibrate position. This punch will be used as the syst em blank the following morning and then taped to the corresponding thermogram.

• Execute the cmdAutoCalibCheck command to verify the analyzer’s performance.

• When the analysis is complete, record the calibration peak counts and calculated injection calibration in the logbook. Any values outside the ranges defined in Section 3.1 should be investigated and rerun.

• Backup the day's data files to disk, if not automatically backed up on a server.

• Remove the printouts and attach them to a file folder labeled with the date and analyzer number. Place on the lab supervisor's desk.

• Turn off the computer monitors.

• Make a final check of the gas cylinder pressures.

• Move the samples and blue ice in the Styrof oam cooler or refrigerator back into the sample storage freezer and verify that the freezer is completely closed.

• If the 25 or 50 μl syringe was used fo r carbonate analysis, thoroughly rinse the syringe with Nanopure water and tightly cap all solutions. Store at 4 °C.

• Lock the carbon analysis room.DRI STANDARD OPERATI NG PROCEDURE Page: 66 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 5 QUANTIFICATION

5.1 Measurement Calculations

Section 3.1.3 contains the equations used to determine measurement values.

5.2 Precision (Uncertainty) Calculations

Precision is determined from replicate measur ements as the average fractional difference between original and replicate analysis concen trations. Concentration uncertainty is the fractional precision times sample concentration. If sample concentration times fractional precision is zero, then the detection limit is used as concentration uncertainty.

The precision calculation program for chemical analysis methods also allows for rejection of outliers and selection of concentration ranges for precision calculations. The uncertainty is calculated using the following formulas:

N cc

cc

CV N

i rii rii 

# ∑

= + −×

= 1

, , 2

2 2 

### )(

MDLcCV Unc i i 

### +×=

Where CV = coefficient of variance

N

= number of samples

c i = concentration of initial analysis

c i,r = concentration of sample “ i ” replicate analysis

Unc = uncertaintyDRI STANDARD OPERATI NG PROCEDURE Page: 67 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 6 QUALITY CONTROL

6.1 Performance Testing

System blanks are performed at the beginning of each day to confirm the system is not introducing bias in the carbon results and to confirm that the laser signal is not temperaturedependent. Contamination is potentially due to:

• Operator practices, such as improper cleaning of tweezers and punch.

• Teflon particles on the push rod getting into the heated zone of the quartz oven.

• Sample boat contamination.

• Contamination of the carrier gas.

• Fibers left on the punch tool or on the flat glass plate during cleaning.

• Contamination from field operator.

• Contamination from normal use of analyzer.

• Maintenance/part replacement.

A temperature-dependent laser signal is potentially due to:

• Physical coupling of the push rod to the boat during the run.

• Boat movement due to loose boat holder.

• A quartz rod (laser light pipe) ready for replacement. As quartz is heated to high temperatures, devitrification (white deposits of SiO 2 ) occurs that leads to a decrease in the laser intensity. The end surface becomes frosty. The bottom light pipe also receives droppings of quartz particles from filter discs during analysis. Thus, the bottom light pipe will deteriorate faster than the upper light pi pe. Microscopic cracks in the quartz rod will increase internal reflectance of the laser ligh t; as the number of these cracks multiply, the effect of temperature on these cracks, a nd thus on the reflectance, becomes an interference in the laser signal.

As described in Section 3.1, the calibration peak at the end of each analysis run serves as a regular standard; the integrated area under the calib ration peak serves as a measure of analyzer performance. In addition, the daily injections of two calibration gases further serve as standards.DRI STANDARD OPERATI NG PROCEDURE Page: 68 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Only a limited set of primary standards (NIST- traceable) currently exist for carbon analysis. These do not include a range of organic compounds from low- to high-molecular weights, with varying degrees of susceptibility to pyrolysis, or EC and carbonate compounds. The cmdAutoCalibCheck command check allows the condition of the catalysts to be monitored and verified.

6.2 Reproducibility Testing

Replicates of analyzed samples are performed at the rate of one per group of ten samples. The replicate is selected randomly and run immediat ely after each group of ten is completed. The random analyzer for the replicate is identified us ing a chart created in Mi crosoft Excel (shown in Figure 6-1) using the random number generator, wh ich results in replicate analysis on the same and different analyzers.

This practice provides a better indication of pot ential differences if samples are analyzed by different laboratories. The μg/cm 2 values for OC, EC and TC ar e compared with the original run. The values should meet the following criteria:

Range Criteria OC, EC & TC < 10 μg/cm 2 < ±1.0 μg/cm 2 OC and TC > 10 μg/cm 2 < 10 % of average of the 2 values EC > 10 μg/cm 2 < 20 % of average of the 2 values Notice that the criteria converge at 10 μg/cm 2 . Replicates which do not meet the above criteria must be investigated for analyzer or sample anomalies. Analyzer anomalies include poor response (as reflected in the calibration peak ar eas) or poor laser signals affecting the splits between OC and EC. Typical sample a nomalies include inhomogeneous deposits or contamination during analysis or from the field sampling location. Inconsistent replicates for which a reason cannot be found must be rerun ag ain unless the filter condition will not allow an additional representative punch to be taken.

When samples are analyzed with an automated sa mple loader, the sample chamber tray will be set up such that the loader number six location will be a replicate of the first sample, the 12 th location a standard spike of sucrose or KHP, and the 18 th location a replicate of the sample in loader position.

6.3 Control Charts and Procedures

Control charts are updated at the beginning of each month. These charts include a month of calibration data and are posted in the carbon room until the end of the month, after which they are filed with the raw analysis results.DRI STANDARD OPERATI NG PROCEDURE Page: 69 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Figure 6-1. Example of carbon analyzer replicate checklist.

. ORIG RUN

CA6 6 6 12 7 8 14 11 8 11 13 13 14 6 9 7 7 6 10 8 11 14 9 8 13 10 9 7

CA7 14 9 7 7 14 12 12 12 6 9 13 8 11 10 7 12 11 6 7 11 7 13 14 10 12 9 6

CA8 11 9 9 8 14 13 10 13 6 14 14 7 10 6 12 11 8 6 6 6 12 13 8 10 12 11 10

CA9 7 8 9 13 8 9 10 13 6 6 8 6 7 9 7 13 11 10 11 7 14 8 12 14 14 13 11

CA10 9 11 6 8 7 13 11 13 9 14 8 12 9 12 9 7 11 7 11 6 12 9 9 8 11 14 10

CA11 10 12 9 14 9 12 13 11 9 10 7 6 10 8 9 6 11 13 11 11 8 13 12 9 10 7 6

CA12 13 7 14 13 12 14 9 12 14 12 13 13 12 6 7 7 9 9 13 12 11 10 8 6 12 14 11

CA13 14 10 11 9 8 9 8 6 13 12 6 11 10 11 8 11 11 12 7 6 7 7 8 12 10 12 6
CA14 9 9 14 14 12 8 14 6 7 14 6 12 8 9 7 13 7 14 12 7 12 12 12 9 9 8 6 CARBON ANALYZER REPLICATE CHECKLIST

Replicate On In order to keep track of the replicates between machines on large projects, please use the checklist below by placing an "X" i n the appropriate box. For example in the first group below, once you have completed 10 runs on the run list, randomly select one QID from those 10 analyses,

find that analyzer # in the "Orig Run" column and replicate it on the analyzer number listed in the next available box in the " Replicate On" section. Place an "X" on that number to indicate the replicate has been done. If an analyzer is not operating, draw a straigh t line through it and go to the next number in the column.

The control chart gives a plot of calibration peak counts as percent deviation from a historical mean versus date. Instances where the calibrati on peak area deviates by more than 10% from the historical mean must be investigated and the cause must be corrected. The historical mean covers results from the previous three months and is updated either quarterly, when the CH 4 calibration gas is changed, when the catalysts are renewed, or when extensive repairs are performed.

6.4 Data Validation

6.4.1 Analysis Flags

During Level 0 validation (see Section 6.4.2), unus ual conditions of the deposit or analysis problems are noted on the analysis printouts. Errors in pre-analysis data entry (e.g., in filter ID, punch size, deposit area) are corrected.

Flags are applied to the Access file created fr om the analysis results (see Section 6.4.2). The analysis flags commonly used are presented in Tabl e 6-1. Note that all results flagged with "v" must include a description of the reason for inva lidating the sample in the remarks field unless a subcode is included which provides additional information (such as v3-“potential contamination”).DRI STANDARD OPERATI NG PROCEDURE Page: 70 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

6.4. 2 Daily Validation

Level 0 validation is performed by manually check ing the tabular and thermogram printouts the day after the analysis is performed. The laborat ory supervisor or a designated technician is responsible for checking the data. The following items are checked on the tabular data (Figure 4-3):

• The filter ID is correct and Punch #.

• For calibration runs, the tabular and thermogr am printouts are checked to make sure the catalysts are operating at required level.

• The analysis date and time is correct.

• The punch area is correct; errors in entry require that the calculated carbon concentrations be recalculated.

• The deposit area is correct; errors in entry require that the calculated carbon concentrations be recalculated by hand.

• The calibration peak area is in the correct range (Section 3.1).

• The initial and the final FID baseline readings are within three counts of each other; excessive FID baseline drift is a cause fo r re-analysis. NOTE: Some very heavily loaded filters will have an FID baseline drift greater than three counts no matter which carbon analyzer the sample is run on; typically a FID baseline drift greater than three counts signals either a problem with the sample (e.g., very light or very heavy loading) or with the carbon analyzer.

• The lower laser split time and the upper lase r split time are within 10 seconds of each other. If the times differ by more than 10 seconds, check that the lower split OC and upper split OC differ by no more than 5%. OC values which differ by more than 5%, unless due to a small change in laser signal resulting from an extremely clean or very dark sample, requires re-analysis. Comments s hould be added to the data file print out as follows:

– If Regular OC Reflectance split is great er than 5% note “RO” in comments field; If Transmittance split is greater than 5% note “TO” in comments field.

Table 6-1. Common DRI Analysis Flags.DRI STANDARD OPERATI NG PROCEDURE Page: 71 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Validation Flag Sub Flag Description b Blank. b1 Field/dynamic blank. b2 Laboratory blank. b3 Distilled-deionized water blank. b4 Method blank. b5 Extract/solution blank. b6 Transport blank.

c Analysis result reprocessed or recalculated. c1 XRF spectrum reprocessed using manually adjusted background. c2 XRF spectrum reprocessed using interactive deconvolution d Sample dropped. f Filter damaged or ripped. f1 Filter damaged, outside of analysis area. f2 Filter damaged, within analysis area. f3 Filter wrinkled. f4 Filter stuck to PetriSlide. f5 Teflon membrane separated from support ring. f6 Pinholes in filter.

g Filter deposit damaged. g1 Deposit scratched or scraped, causing a thin line in the deposit. g2 Deposit smudged, causing a large area of deposit to be displaced. g3 Filter deposit side down in PetriSlide. g4 Part of deposit appears to have fallen off; particles on inside of PetriSlide. g5 Ungloved finger touched filter. g6 Gloved finger touched filter. h Filter holder assembly problem. h1 Deposit not centered. h2 Sampled on wrong side of filter. h4 Filter support grid upside down- deposit has widely spaced stripes or grid pattern. h5 Two filters in PetriSlide i Inhomogeneous sample deposit. i1 Evidence of impaction - deposit heavier in center of filter. i2 Random areas of darker or lighter deposit on filter. i3 Light colored deposit with dark specks. i4 Non-uniform deposit near edge - possible air leak.DRI STANDARD OPERATI NG PROCEDURE Page: 72 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Table 6-1, continued.

Validation Flag Sub Flag Description

m Analysis results affected by matrix effect. m1 Organic/elemental carbon split undeterm ined due to an apparent color change of non-carbon particles during analysis; all measured carbon reported as organic. m2 Non-white carbon punch after carbon analysis, indicative of mineral particles in deposit. m3 A non-typical, but valid, laser response was observed during TOR analysis. This phenomena may result in increased uncertainty of the organic/elemental carbon split. To tal carbon measurements are likely unaffected. m4 FID drift quality control failure

n Foreign substance on sample. n1 Insects on deposit, removed before analysis. n2 Insects on deposit, not all removed. n3 Metallic particles observed on deposit. n4 Many particles on deposit much larger than cut point of inlet. n5 Fibers or fuzz on filter. n6 Oily-looking droplets on filter. n7 Shiny substance on filter. n8 Particles on back of filter. n9 Discoloration on deposit.

q Standard. q1 Quality control standard. q2 Externally prepared quality control standard. q3 Second type of externally pr epared quality control standard. q4 Calibration standard.

r Replicate analysis. r1 First replicate analysis on the same analyzer. r2 Second replicate analysis on the same analyzer. r3 Third replicate analys is on the same analyzer. r4 Sample re-analysis. r5 Replicate on di fferent analyzer. r6 Sample re-extrac tion and re-analysis. r7 Sample re-analyzed with same result, original value used.

s Suspect analysis result.DRI STANDARD OPERATI NG PROCEDURE Page: 73 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Table 6-1, continued.

Validation Flag Sub Flag Description

v Invalid (void) analysis result. v1 Quality control standard check exceed ed ± 10% of specified concentration
range. v2 Replicate analysis failed accep table limit specified in SOP. v3 Potential contamination. v4 Concentration out of expected range. v5 Instrument error v6 Operator error

w Wet Sample. w1 Deposit spotted from water drops.

y Data normalized y1 XRF data normalized to a sulfate/sulfur ratio of three y2 Each species reported as a percentage of the measured species sum

– If Regular EC Reflectance split is great er than 20% note “RE” in comments field; If Transmittance split is greater than 5% note “TE” in comments field.

• Calculated carbon values for calibration injection runs are within 10% of the current mean value for the injected gas type on that analyzer.

Acceptance runs for pre-fired qua rtz filters result in < 1.5 μg/cm 2 OC, < 0.5 μg/cm 2 EC, and < 2.0 μg/cm 2 TC for IMPROVE_A thermal protocol. F ilters which exceed these levels must be re-fired or rejected.

Items which are found to be okay are underlined in red. Items which have problems are circled in red.

The thermograms are checked for the following (Figure 4-4):

• The initial FID baseline is flat, indicating th at the analyzer has been thoroughly purged before analysis began.

• The final FID baseline prior to the calibration p eak is within three m illivolts of the initial FID baseline; excessive drift is cause for reanalysis.DRI STANDARD OPERATI NG PROCEDURE Page: 74 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• The laser reflectance signal during the first tw o minutes, prior to sample introduction to the “Analysis” position, appears near the botto m of the graph and shifts position once the sample is in the “Analysis” position. The transmittance signal will be out-of-scale until the sample is in the “Analysis” position.

• The laser signal should dip below the initial laser line until O 2 is introduced, at which point the signal should rise steeply. (For most samples, charring does occur). High temperature soot samples may not show this characteristic.

• The temperature readings reflect stable and smooth temperatures at each level and quick transitions between levels.

• Problems or deviations from normal should be circled in red. If the sample punch taped to the thermogram is not white, it is also circled.

If examination of the tabular and thermogram prin touts results in a decision that a sample should be reanalyzed, write "Rerun" in red on the printouts and prepare a re-analysis list. This list should be posted immediately after the validation is complete, and those samples should be rerun as soon as they can be conveniently fit into the current day's analyses.

Evidence of persistent analyzer problems must be resolved, either by physically examining the analyzer or reviewing the problems with the analyzer operator.

6.4.2.1 Validation of Final Data File

The following steps are followed to create an Excel or dbf file containing carbon data and to perform Level "I" validation on it:

• Each analyzer will have an Access database containing all of the raw carbon data.

• A query (manual or automated by connected server) is used to generate the project data in μg/cm 2 or μg/filter and a validation report is then generated from this query.

• The output of the Access query is saved or exported as an Excel file or database report for data validation and processing. Th e MS Excel file naming convention calls for a name in the following format:

xxOETnnt.xls

where:DRI STANDARD OPERATI NG PROCEDURE Page: 75 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
xx is the two-character project identifier OET is organic/elemental carbon nn is the two- or three-digit batch numbe r (generally used to distinguish between different projects for the same client or between sampling quarters for an extended project) t is the sample type based on sampler technology: A is agricultural burn emissions dilution sampler C is combination particle/gaseous sampler D is dichotomous sampler for PM 2.5 , PM coarse , and PM 10 G is gaseous H is high-volume sampler I is IMPROVE/NPS sampler P is MiniVol Sampler Q is audit samples R is resuspension chamber S is sequential filter sampler (SFS) W is wet Deposition X is unknown Y is y-sampler (DRI source sampler)

• The final MS Excel or dbf file name is specified on the analysis list posted in the carbon room.

• Begin validation by matching the filters liste d on the analysis list with the filters listed on the MS Excel or database printout . There must be at least one entry on the printout for every filter listed on the analysis list.

• Flag field and lab blanks while the list is being reviewed by placing "b1", "b2", "b3", or "b6" in the second column of the printout. Because the MS Excel or database printout is sorted by ID number, replicates and reruns will be grouped together.

• Indicate missing data by writing the missing f ilter ID in the margin with an arrow drawn to the appropriate place of inserti on. Scan the printout for unusual IDs which may have been mistyped or misread by the scanner during analysis. Generally, these will appear at the beginning or end of the pr intout, due to the sorting process. Make sure that all samples listed on a rerun list appear on the printout.

• Resolve all missing data. Scan the deposit ar ea column for incorrect entries. Circle the incorrect entries to ensure that corr ected values replace those currently in the database.DRI STANDARD OPERATI NG PROCEDURE Page: 76 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Scan the filter IDs for multiple entries of ID numbers. Under normal conditions, the only times multiple entries should occur are re runs and replicates. All multiple entries must be flagged to indicate the reason for their existence.

• Scan for missing runs. The most common exam ple is the first run being aborted or lost for some reason, and the only entry in the MS Excel file is the second run. An entry for the first run must be inserted, fla gged as invalid, and labeled as to the reason it was invalid. All punches taken from th e filters MUST be accounted for and documented in the file.

• Pull the analysis folders and go through the analysis summaries and thermograms one by one. Check for the conditions listed in Section 6.4.2

– Reflectance and Transmittance Regular OC Lower Split and Upper Split are within 5% and Regular EC Lower Split and Upper Split are within 20%. OC values which differ by more than 5%, unless due to a small change in laser signal resulting from an extremely clean or very dark sample, requires reanalysis. Comments should be added to the print out as follows:

• If Regular OC Reflectance split is greater than 5% note “RO” in comments field; If Transmittance split is greater than 5% note “TO” in comments field.

• If Regular EC Reflectance split is greater than 20% note “RE” in comments field; If Transmittance split is greater than 5% note “TE” in comments field.

– Punch discoloration after analysis is complete (See Table 6.1 for m2 flag)

• Verify and resolve all circled items and missing flags.

– Determine if analyses flagged by the ope rator are legitimate. These flags are determined by the operator at the end of the analysis run (Section 6.4) and are defined in Table 6-2.

– If the temporary flag is not warranted, draw a line through the flag to indicate that it should be removed.

– If the sample should be rerun, add it to a rerun list.

– If the analysis has some anomaly, but still appears to be legitimate, either flag or add notes to the comments field as appropriate.DRI STANDARD OPERATI NG PROCEDURE Page: 77 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

– Analysis flags are defined in Table 6-1.

– Invalid samples without a definitive voi d flag must have an entry in the comments field to describe the reason that the sample is invalid. Typical notes and comments are presented in Table 6-3.

• Scan the OC and EC columns looking for unusually high or low values. At this time make sure that the field blanks and/or lab blanks are all close to one another. Circle any possible outliers for further investigation.

• Compare replicates against original r un. The values should meet the following criteria: Range Criteria OC, EC & TC < 10 μg/cm 2 < ±1.0 μg/cm 2 OC and TC > 10 μg/cm 2 < 10 % of average of the 2 values EC > 10 μg/cm 2 < 20 % of average of the 2 values

• Check the OC/TC ratio. Typical rural samples should not be less than 0.65. Circle any possible outliers for further investigation.

• Scan for records where EC is greater than OC. These may require additional investigation, depending on loading and samp le source. Circle records for further investigation.

• Scan blanks for OC being greater than 3.95 × deposit area and for EC greater than the deposit area. Rerun any unusually high blanks.

• Compare primary and secondary filters for validity. Secondary filters should have OC and EC measurements less than the co rresponding primary filter. Typical rural secondary filters should have EC < 3.8. OC should be less than or equal to 18. Circle any records that require further investigation.

• All operator-generated flags must be either converted to standard analysis flags (Table 6-1) or removed. The flags in Tabl e 6-2 are temporary flags only and are not recognized as legitimate analysis flags at DRI.

• After all thermograms have been review ed and all possible reruns have been identified, post the rerun list in the carbon r oom and have the reruns done as soon as possible.DRI STANDARD OPERATI NG PROCEDURE Page: 78 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Table 6-2. DRI Carbon Analysis Operator Temporary Data Validation Flags.

Flag Description

EI Error in sample ID

EA Error in sample deposit area

ST Suspect temperature profile

SF Suspect FID signal

SL Suspect laser signal

Mi Miscellaneous problem

m2 Non-white sample punch after analysis

v Invalid run

r Replicate

b Blank

i Inhomogeneous

f Filter media damaged

g Sample deposit damaged

d Sample dropped

n Foreign substance on filter

w Sample wetDRI STANDARD OPERATI NG PROCEDURE Page: 79 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

Table 6-3. DRI Carbon Analysis Validation Comments

Comments Description "Anomalous laser" Despite good initial laser, laser signal drifted above initial laser signal before dropping (typical of auto emissions).

"Operator error" Used with "v" flag; operator exited program unexpectedly.

"Analyzer malfunction" Used with "v" flag; analyzer malfunction or problem beyond the control of the operator such as plugged FID, broken oven heater,
etc.

"Poor replicate" Replicate is outside th e normal criteria, but no reason can be found for the discrepancy.

"Poor initial laser" Used with "v" flag; se vere coupling or boat not pushed in time for calculation of initial laser signal.

"Potential contamination" Used with "v" flag; rer un of sample yields lower values or different peaks. Typically used with blanks or reruns of replicates.

“Power failure” Used with "v" flag; power surge or power failure.DRI STANDARD OPERATI NG PROCEDURE Page: 80 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

• Review the data from the reruns, looking for inconsistencies. Confirm that the reasons for the rerun have been addressed. Ma rk the printout with the new values for manual insertion into the MS Excel or database file. Previous runs must be flagged as invalid or the reruns flagged as replicates.

• Finally, all comments, flags, insertions, a nd other changes made to the printout are entered into the MS Excel or database f ile. After all changes are made, generate a new printout. Label the new printout with the file name and printout date. Assemble a copy of the printout and the MS Excel or da tabase file for the person putting the final report together.DRI STANDARD OPERATI NG PROCEDURE Page: 81 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 7 REFERENCES

Chen, L.-W.A.; Chow, J.C.; Watson, J.G.; Moosmü ller, H.; and Arnott, W.P. (2004). Modeling reflectance and transmittance of quartz-fiber filter samples containing elemental carbon particles: Implications for thermal/optical analysis. J. Aerosol Sci.
, 35 (6):765-780.

Chow, J.C.; Watson, J.G.; Pritchett, L.C.; Pierson, W.R.; Frazier, C.A.; and Purcell, R.G. (1993). The DRI Thermal/Optical Reflectance carbon an alysis system: Description, evaluation and applications in U.S. air quality studies. Atmos. Environ.
, 27A (8):1185-1201.

Chow, J.C.; Watson, J.G.; Crow, D.; Lowenthal, D.H.; and Merrifield, T.M. (2001). Comparison of IMPROVE and NIOSH carbon measurements. Aerosol Sci. Technol.
, 34 (1):23-34.

Chow, J.C.; and Watson, J.G. (2002). PM 2.5 carbonate concentrations at regionally representative Interagency Monitoring of Protected Visual Environment sites. J. Geophys. Res.
, 107 (D21):ICC 6-1-ICC 6-9.

Chow, J.C.; Watson, J.G.; Chen, L.-W.A.; Ar nott, W.P.; Moosmüller, H.; and Fung, K.K. (2004). Equivalence of elemental car bon by Thermal/Optical Reflectance and Transmittance with different temperature protocols. Environ. Sci. Technol.
, 38 (16):4414- 4422.

Chow, J.C.; Watson, J.G.; Chen, L.-W.A.; Ch ang, M.C.; and Paredes-Miranda, G. (2005). Comparison of the DRI/OGC and Model 2001 Thermal/Optical carbon analyzers. Prepared for the IMPROVE Steering Committee, Fort Collins, CO, by Desert Research Institute, Reno, NV.

Chow, J.C.; J.G. Watson; L.-W.A. Chen; M.C.O. Ch ang; N.F. Robinson; D. L. Trimble; and S.D. Kohl (2007). The IMPROVE_A Temperatur e Protocol for Thermal/Optical Carbon Analysis: Maintaining Consistency with a Long-Term Data Base. JAWMA
, 57 :1014- 1023.

Desert Research Institute (2007). Pre-firing of quartz filters for carbon analysis. SOP #2-106r6. Desert Research Institute: Reno, NV.

Fung, K.K. (1986). Personal communication.

Huntzicker, J.J. (1986). Personal communication.DRI STANDARD OPERATI NG PROCEDURE Page: 82 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2
Johnson, R.L. (1981). Development and evaluation of a thermal/optical method for the analysis of carbonaceous aerosol. M.S. Thesis, Oregon Graduate Center, Beaverton, OR.

Johnson, R.L.; Shah, J.J.; Cary, R.A.; and Huntzick er, J.J. (1981). An automated thermal-optical method for the analysis of carbonaceous aerosol. In Atmospheric Aerosol: Source/Air Quality Relationships , E.S. Macias and P.K. Hopke, Ed s. American Chemical Society, Washington, DC, pp. 223-233.

Lin, C.; and Friedlander, S.K. (1988). Soot oxidati on in fibrous filters. 2. Effects of temperature, oxygen partial pressure, and sodium additives. Langmuir
, 4 (4):898-903.

Novakov, T. (1981). Microchemical ch aracterization of aerosols. In Nature, Air and Methods of Microchemistry , H. Malissa, M. Grasserbauer, and R. Belcher, Eds. Springer-Verlag, Wein, Graz, Austria, pp. 141-165.

Novakov, T. (1982). Soot in the atmosphere. In Particulate Carbon: Atmospheric Life Cycle
, G.T. Wolff and R.L. Klimisch, Eds. Plenum Press, New York, NY, pp. 19-41.

Rau, J.A. (1986). Residential wood combustion aer osol characterization as a function of size and source apportionment using chemical ma ss balance modeling. Ph.D. Dissertation, Oregon Graduate Center, Beaverton, OR.

Rosen, H.; Hansen, A.D.A.; Dod, R.L.; Gundel, L.A.; and Novakov, T. (1982). Graphitic carbon in urban environments and the Arctic. In Particulate Carbon: Atmospheric Life Cycle
, G.T. Wolff and R.L. Klimisch, Eds. Plenum Press, New York, NY, pp. 273-294.DRI STANDARD OPERATI NG PROCEDURE Page: 83 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### 8 CHANGE DOCUMENTATION

7/24/2008 – Made following changes to document:

• Revised cover page to include signature lines

• Updated Section 2 (Apparatus, Instrumenta tion, Reagents and Forms) with current information and forms

• Updated Figures 2-1 and 2-3 with more current and detailed information

• Renamed Quantification to Calibration and moved to Section 3

• Moved Temperature Calibration to Section 3

• Updated text and formulas in Secti on 3.1.3.1 under preparation of standards for clarification and accuracy.

• Updated Figure 3-4 with new worksheet and new volumes.

• Moved Procedures to Section 4 and updated to include additional details where needed

• Moved Quantification to Section 5; added precision calculations.

• Updated Quality Control (Section 6)

• Updated References as needed (Section 7)

• Added Section 8 (Change Documentation)

• Added Section 9 (Appendix A)DRI STANDARD OPERATI NG PROCEDURE Page: 84 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2



### APPENDIX A: Abbreviations and Acronyms

°C Degrees Celsius μg/m 3 Micrograms per cubic meter μl Microliters Cal Gas Calibration Gas Calibration Injection The injection of calibration gases, either CO 2 or CH 4 , into the sample stream at the beginning and end of each work day to check instrument performance. Calibration Peak The FID peak resulting from the automatic injection of methane calibration gas (CH 4 /He) at the end of each analysis run for each sample. All integrated peak areas are divided by the calib ration peak area and multiplied by an instrument-specific calibration factor to obtain μg carbon per sample punch. C hemicals Used:

H 2 Hydrogen HF Hydrofluoric Acid HCl Hydrochloric Acid He Helium CO 2 Carbon Dioxide CH 4 Methane O 2 Oxygen Na Sodium SiO 2 Silicon Dioxide K Potassium KHP Potassium hydrogen pthalate V Vanadium Cr Chromium Mn Manganese MnO 2 Manganese Dioxide Co Cobalt Ni Nickel Cu Copper Pb Lead

DRI Desert Research Institute EC Elemental Carbon EC1 Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere at 580 °C. EC2 Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere from 580 to 740 °C. EC3 Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere from 740 to 840 °C. Elemental Carbon (EC) Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere at 580, 740, and 840 °C minus any pyrolyzed OC.DRI STANDARD OPERATI NG PROCEDURE Page: 85 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

FID Flame Ionization Detector FID Split Time The time at which the laser sp lit occurs plus the transit time required for thermally evolved carbon to travel from the sample punch to the FID. GC Gas Chromatography GC/MS Gas Chromatography/Mass Spectrometry High Temperature EC Carbon evolved from the filter punch in a 98% He/2% O 2 atmosphere at 740 and 840 °C minus any pyrolyzed organi c carbon present in these two peaks. This is EC minus the first EC peak (EC1). High Temperature OC Carbon evolved from the filter punch in a He-only atmosphere at 280, 480, and 580 °C plus pyrolyzed organic car bon. This is OC minus the first OC peak (OC1). IMPROVE Interagency Monitoring of PROtected Visual Environments IMPROVE_A Thermal Protocol A thermal protocol is used in carbon analyzers to quantify carbon fractions evolved at different temperature plateaus. The IMPROVE_A thermal protocol derives from the IMPROVE thermal protocol initiated in 1987 (Chow et al., 2005). Laser Split The separation between OC a nd EC, which depends on the laser-measured reflectance and/or transmittance of the filter punch returning to its initial value. At this point all pyrolyzed OC has been removed and EC is beginning to evolve. Lower Split Time The time at which the laser-measured reflectance and/or transmittance of the filter punch reaches its initial value mi nus the precision of the laser signal (currently defined as 10 counts). LQL Lower quantifiable limit M Mole MDL Minimum detection limit NIST National Institute of Science and Technology OC Organic Carbon OC1 Carbon evolved from the filter punch in a He- only (>99.999%) atmosphere from ambient (~25 °C) to 140 °C. OC2 Carbon evolved from the filter punch in a He- only (>99.999%) atmosphere from 140 to 280 °C. OC3 Carbon evolved from the filter punch in a He- only (>99.999%) atmosphere from 280 to 480 °C. OC4 Carbon evolved from the filter punch in a He- only (>99.999%) atmosphere from 480 to 580 °C. OP The carbon evolved from the time that the carrier gas flow is changed from He to 98% He/2% O 2 at 580 °C to the time that the laser- measured filter reflectance (OPR) or transmittance (O PT) reaches its initial value. A negative sign is assigned if the laser split occurs before the introduction of O 2
. OPR Pyrolyzed carbon measured by reflectanceDRI STANDARD OPERATI NG PROCEDURE Page: 86 of 86 Date: July 2008 Title: DRI Model 2001 Thermal/Optical Carbon Analysis Number: 2-216r2 (TOR/TOT) of Aerosol F ilter Samples - Method IM PROVE_A Revision: 2

OPT Pyrolyzed carbon measured by transmittance Organic Carbon (OC) Carbon evolved from the filter punch in a He- only (>99.999%) atmosphere at 140, 280, 480 and 580 °C plus pyrolyzed organic carbon. This is the same as Volatile Organic Carbon (VOC) plus high- temperature OC. psi Pounds per square inch Pyrolysis The conversion of OC compounds to EC due to thermal decomposition; this may be envisioned as "charring" during the organic portion of the analysis. QA Quality Assurance QC Quality Control Regular Split Time The time at which the laser-measured reflectance and/or transmittance of the filter punch reaches its initial value. SiO 2 Silicon Dioxide STN Speciation Trends Network TC Total Carbon TOR Thermal/Optical Reflectance TOT Thermal/Optical Transmittance Total Carbon (TC) All carbon evolved from the filter punc h between ambient and 840 °C under He and 98% He /2% O 2 atmospheres. VOC Volatile Organic Carbon UHP Ultra-High Purity Upper Split Time The time at which the laser-m easured reflectance and/or transmittance of the filter punch reaches its initial value pl us the precision of the laser signal (currently defined as 10 counts). Δ T Temperature Deviation