UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 4 ATLANTA FEDERAL CENTER 61 FORSYTH STREET "'% ,oRO~cG.(I' ATLANTA, GEORGIA 30303-8960



## JAM 

## 1 

# 7 ;?008

Joseph 

### Kahn, Director, Division of Air Resource Management Florida Department of

Environmental Protection 2600 Blair Stone Road Tallahassee, Florida 32399-2400

Dear Mr. 

### Kahn:

Thank you for your January 3,2008, letter and the January 11,2008, e-mail concerning the application of the new Interagency Monitoring of Protected Visual Environments (IMPROVE) equation. The January 11,2008, e-mail provided additional documentation to implement the new equation. You requested the use of this new methodology to estimate visibility impacts from Florida facilities to implement the Best Available Retrofit Technology (BART) requirement of the Regional Haze Rule.

The new methodology uses a spreadsheet developed by the Visibility Lmprovement - 

### State and Tribal Association of the Southeast (VISTAS) Regional Planning Organization to postprocess the visibility modeling output from the CALPUFF and CALPOST models. The spreadsheet implements the new IMPROVE equation that was adopted by the IMPROVE Steering Committee in December 2005. EPA Region 4 has previously commented that the new methodology is an alternative modeling approach that must meet the requirements in Section 3.2 of Appendix W, Guideline 

### on Air Quality Models, contained in title 40 Code of Federal Regulations Part 

### 5 1.



### We have reviewed the documentation supporting use of the new methodology that was provided in your letter and e-mail. This documentation included: the rationale explaining the need to use the new IMPROVE equation; a discussion of the performance of the new equation versus measured values; and submittal of the modified post-processing methodology. Based on the demonstration provided in your documentation, we approve your request.

We appreciate your desire to protect and preserve the environment. If we may be of Wher assistance, please feel free to contact Beverly Banister of my staff at (404) 562-9326.

Sincerely,

A

\\_/ 

### J. I. Palmer, Jr. Regional Administrator

Internet Address IURL) http Iiwww epa gov RecycledlRecyclable Pi~nted wlth Vegetable Oil Based Inks on Recycled Pap% ihhn~rnm 'W? Postcors~~rner)

# Florida Department of Charl~e Crist Governor 

# Environmental Protection Jeff Kottkamp
Bob Martinez Center I t. (ioveruor

2600 Blair Stone Road Tallahassee, Florida 32399-2400 Michael W. Sole Secretary



### Mr. 

### J. I. Palmer, Regional Administrator U.S. EPA Region 4 Atlanta Federal Center 6 

### 1 Forsyth Street, SW Atlanta, Georgia 30303-8909 January 3,2008

CJ r i



### Subject: Request for Approval to Use New IMPROVE Equation for BART Modeling -7 

### -.



## - Dear Mr. Palmer, w -J



### The Florida Department of Environmental Protection (DEP) has been working with Visibility Improvement States and Tribal Association of the Southeast (VISTAS) and U.S. EPA, Region 4 staff

to implement the Best Available Retrofit Technology (BART) requirements of the Regional Haze Rule. As part of this process, the need for a methodology to post-process CALPUFFICALPOST modeling data to implement the new IMPROVE equation was identified. VISTAS contracted with Dr. Ivar Tombach to develop such a methodology. The resulting spreadsheet and supporting information were submitted to EPA and the Federal Land Managers (FLM's) for review. EPA Region 4 staff commented that they consider this post-processing methodology a non-regulatory modeling application requiring compliance with section 3.2 of Appendix W, Part 5 1 : 

### Guideline on Air Quality Models and that each state must obtain approval for its use &om the EPA Regional Administrator. In response to these comments and for the reasons discussed below, the following additional information is provided and formal approval of use of this alternative by the affected sources for BART exemption and demonstration modeling is requested.

Rationale for Need for Use of New IMPROVE Equation The new IMPROVE equation has been shown to better represent the effects of particulate matter light extinction compared to the previous (old) equation, and has been developed using the latest scientific understanding and data. Specific improvements are outlined in Enclosure 1. With this combination of revisions to the IMPROVE equation, the resulting apportionment of extinction to various components is more accurate on the haziest and clearest days. This is important for development of emission control strategies since the benefits of control of concentrations of each species will be represented more correctly with the new equation. Further discussion of these

reasons is discussed in Enclosure 1.

All of the Florida Class I 

### areas, and many of the BART-eligible sources, are along the coast. The ability to approximately represent the contribution of sea salt for these sources is important in determining their contribution to haze and evaluating the benefit of potential control strategies. U.S. 

### EPA Region 4, the National Park Service, and the U.S. Fish and Wildlife Service determined that adding site-specific data to account for the impact of sea salt and Rayleigh scattering to the old

### Mr. Palmer January 

### 3,2008 Page 

### 2

IMPROVE equation is not appropriate, but rather the entire new IMPROVE equation should be used. The spreadsheet developed by Dr. Tombach to implement the entire new IMPROVE equation for use with CALPUFF uses CALPOST output to calculate light extinction in accordance with the new IMPROVE equation. In their review of the spreadsheet and supporting documentation (see Enclosure 3), 

### EPA Region 4 staff commented that the VISTAS methodology contained in the spreadsheet appropriately implements the new IMPROVE equation, with the exception of the nitrogen dioxide term. EPA Region 4 further stated that with the addition of their recommendation for addressing the NOz term, the VISTAS methodology to incorporate the new IMPROVE equation is acceptable on a case-by-case basis upon consultation with the EPA Regional Office. VISTAS, through Dr. Tombach, have revised the spreadsheet to include the NO2 term and Florida is implementing the spreadsheet by making the conservative assumption that all NOx is in the form of N02.

Equation Performance Versus Measured Values A comparison of the old versus the new IMPROVE equation and nephelometer data at several Class I 

### areas is included in Enclosure 1. The old IMPROVE equation tends to show a low bias on high extinction days. The new equation shows a better match on high extinction days with a slightly high bias. The correlation coefficients are often slightly lower for the new equation than the old equation because there is slightly more scatter at the low end of the equation. Nephelometer data are not available in the Florida Class I 

### areas, however, performance of the equations for the coastal Cape Romain Class I area on the coast of South Carolina (see Enclosure 1) and the Okefenokee Class I area immediately adjacent to Florida (see Enclosure 2) presents some common geography to Florida.

Again, we ask your approval for the use of the VISTAS methodology incorporating the new IMPROVE equation for Florida's BART-eligible sources. We believe that the improved science with the inclusion of important Florida-specific factors such as sea salt and elevation-corrected Rayleigh scattering provide ample rationale for use of the new IMPROVE equation for all BARTeligible sources in the state. If you or your staff has any questions regarding this matter, please contact Tom Rogers of my staff at 

### (850) 921-9554 or e-mail at Tom.Rogersi@de~.state.fl.us



### . Thank

you for consideration of issue.

Sincerely,

ivision of Air Resource Management

Enclosures

Cc: Dick Shutt, EPA Region 4 Brenda Johnson, EPA Region 4 

### Larry George, FDEP

- 

### DARM

### Why Use the New 

### IMPROVE Algorithm?

The new IMPROVE algorithm, which has been approved by the IMPROVE Steering Committee, is a much better representation of the effects of particulate matter on light extinction than the old IMPROVE algorithm. Excellent justification of this conclusion is provided in the November 2005 report of the IMPROVE Steering Committee, "Revised IMPROVE Algorithm for Estimating Light Extinction from Particle Speciation Data."

The new algorithm incorporates changes that represent much of what has been learned about the relationship between particulate matter component concentrations and light extinction in the more than a decade since the old algorithm was developed. The main reasons that justify using the new algorithm instead of the old one are the following:

1. The new algorithm overcomes the biases of the old algorithm on the haziest days (when the old algorithm underestimates light extinctionj and on the clearest days (when the old algorithm overestimates extinction). This improvement can be seen by comparing measured light extinction from nephelometers with light extinction calculated using either the original IMPROVE equation or the new IMPROVE equation. Figures 1,2, and 3 in this summery illustrate the performance of the

new and old equations compared to nephelometer data for Great Smoky Mountains and Shenandoah National Parks and Cape Romain Wildlife Refuge. Additional examples are available in figures and the appendix of the IMPROVE report rcfereirced above and on the Air Resource Specialists ftp site (ftp://ftp.airresource.~omNISTAS/4c~Neph_Compare/.)

2. The new algorithm recognizes that light extinction efficiencies vary from location

to location and time to time as the size distribution of the aerosol changes, and it reflects this variation by increasing the extinction efficiency as the concentrations of sulfates, nitrates, and organics increase. It also recognizes that the humidityrelated growth rates of particles differ depending on their sizes. As a result, the

new algorithm generally does a better job of representing light extinction at individual sites than does the old algorithm, as indicated by the reduced fractional biases in each RPO region shown in Tables 3 and 5 (versus Tables 2 and 4) from the report mentioned above and copied into this summary.

3. The new algorithm recognizes research findings that show that fine sea salt can be

an important contributor to light extinction in coastal areas, and thus includes a

new term that reflects its contribution and its hygroscopic growth with increasing relative humidity. The old algorithm ignores sea salt, probably because it was originally developed mainly for inland Class I areas in the inter-mountain West (although incorporating sea salt into the calculation was already considered in a University of California at Davis memo in 1995).The new algorithm acknowledges that substantial recent research has shown that the mass concentration of particulate organic matter (often denoted by OMC 

### in IMPROVE publications) in rural areas is a greater multiple of the measured OC concentration than the 1.4 value used 

### in 

### the old algorithm. The new algorithm updates the factor to a more-appropriate1.8.

The new algorithm recognizes that there may be times (near urban areas or 

### in some source emission plumes) when Iight absorption by NOz gas is a meaninghl contributor to light extinction, and 

### thus includes a new term based on the NO2 concentration.

The new algorithm recognizes that the assumption of constant Rayleigh scattering of 

### 10 ~m*' (representative of an elevation of about 

### 5000 feet) may have been adequate when only inter-mountain West sites were considered, but is a distortion for sites close to sea level or with very hot or cold climates. It thus allows for sitespecific values of the Rayleigh scattering.

At any given location, the net result of aII these changes 

### is typically small on average because some changes result 

### in increases in extinction and some in decreases, but the apportionment of that extinction to the various components is more accurate with the new algorithm, especially on the haziest and clearest days. This is particularly important for the development of emission management strategies, because the benefits of control of concentrations of each species will be represented more correctly with the new algorithm.

Figure 1. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old IMPROVE Algorithm and Daily 

### f(RH), Great Smoky Mountains National Park, 1995- 2004.

- -- - 

### New IMPROVE Old 

### (MPROVEFigure 2. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old IMPROVE Algorithm and Daily f(RH), Shenandoah National Park, 1996-2004.

New IMPROVE Old IMPROVE

Figure 3. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old IMPROVE Algorithm and Daily f(RH), Cape Romain Wildlife Refuge, 2004.

t.. New IMPROVE Old IMPROVEThe Tables below were copied from the report "Revised 

### IMPROVE Algorithm for 

### Estimating Light Extinction from Particle Speciation Data" available from the VIEWS website.

Table 2. Averaged fractional bias by RPO for the current IMPROVE algorithm with quintiles based on measured Light scattering (criterion 1). Bold font highlights the bias values that are lower than corresponding values in Table 3.

RPO Quintile 1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.67 0.18 0.10 0.02 -0.11 0.17 MANE 0.93 0.27 0.19 0.10 0.01 0.28 VISTAS 0.59 0.21 0.1 1 0.02 -0.13 0.16 WRAP 1 .07 0.37 0.18 0.07 -0.08 0.32

Table 3. Averaged fractional bias by 

### RPO for the current new proposed algorithm with quintiles based on measured tight scattering (criterion 1). Bold font highlights the bias values that are lower than corresponding values in Table 2.

RPO Quintile I Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.51 0.08 0.02 -0.03 -0.08 0.10 MANE 0.74 0.14 0.06 0.01 -0.02 0.17 VISTAS 0.50 0.16 0.1 1 0.06 -0.01 0.16 WRAP 0.84 0.25 0.08 0.01 -0.10 0.21

Table 4. Averaged fractional bias by 

### RPO for the current IMPROVE algorithm with quintiles based on estimated light scattering (criterion 2). Bold font highlights the bias values that are lower than corresponding values in Table 5.

RPO Quintile 1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.42 0.19 0.18 0.09 -0.01 0.17 MANE 0.35 0.27 0.30 0.33 0.15 0.28 VISTAS 0.38 0.19 0.14 0.08 0.01 0.16 WRAP 0.58 0.37 0.26 0.25 0.15 0.32

Table 

### 5. Averaged fractional bias by RPO for the current new proposed algorithm with quintiles based on estimated light scattering (criterion 2). Bold font highlights the bias values that are lower than corresponding values in Table 4.

RPO Quintile 1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.23 0.11 0.08 0.06 0.02 0.10 MANE 0.15 0.14 0.15 0.19 0.21 0.17 VISTAS 0.25 0.14 0.08 0.13 0.21 0.16

WRAP 0.37 0.19 0.19 0.16 0.17 0.2 1

### Enclosure 

### 2

Comparison of New and Old IMPROVE Equations at Okefenokee Class I Area

All Days



### 0 50 100 150 200 250 300

24-hr Nephelometer bsp (~m-')

All Days



### .-



### y 

## = 0.72~ 

### + 18.46

24-hr Nephelometer bsp (~m-')

## lvar Tombach, 

## Ph. D.

8mrn.m&%fl+ 753 Grada Ave. Camarillo, CA 93010 805 388-2341 805 445-9424 fax itombach@aol.com



## Instructions: A Postprocessor for Recalculating CALPOST Visibility Outputs with the New IMPROVE Algorithm

Version 2 

### 14 October 2006

Introduction

CALPOST can be used to processes outputs from CALPUFF modeling of a source's emissions to calculate the 24-hr average visibility impairments caused by primary and secondary particulate matter attributable to emissions fiom the modeled source. Those increments are presented in two tables, both labeled "Ranked Daily Visibility Change", in the CALPOST output (.LST) file. The table of interest to us has the subtitle "Modeled Extinction by Species" and lists the dates and locations of such incremental impacts in light extinction (beXt) in ranked order, starting with the one that represents the largest percentage change in light extinction.'

In addition, with a different setup of the control file CALPOST.INP, the CALPOST postprocessor can be used to calculate 24-hr averages of NO, concentrations. As described below, the outputs fiom that additional CALPOST run can be used to assess the visibility impact of the NO2 gas in the source plume.

Visibility effects due to particulate matter are calculated in CALPOST from CALPUFF-modeled particulate matter component concentrations using effectively the "traditional" IMPROVE algorithm. CALPOST allows for choice of the humidity scattering enhancement function (f(RH))

to be used with the IMPROVE algorithm; for modeling in connection with the US EPA's Regional Haze Regulations (RHR), the appropriate form of f(RH) is the one described and tabulated in the EPA's 2003 guidance for tracking progress under the RHR. Visibility effects due

to NO2 are not considered in the CALPOST visibility calculation.

Recently, the IMPROVE Steering Committee developed a new algorithm for estimating light extinction from particulate matter component concentrations. This algorithm (the "new IMPROVE algorithm") provides a better correspondence between the measured visibility and

I The other table in the CALPOST visibility output file, with the subtitle "% of Modeled Extinction by Species", provides equivalent results in terms of changes in the haze index, in deciviews. The two tables represent the same results, with identical ranking of events, while just using different (but mathematically related) metrics.

### that calculated from particulate matter component concentrations. The new algorithm differs in several substantive ways from the traditional one:

The extinction efficiencies of sulfates, nitrates, and organics have been changed and are

now functions of their concentrations. The extinction efficiencies of sulfate and nitrate

are no longer identical, although the new hygroscopic scattering enhancement factors applied to them are the same.

The concentration of particulate organic matter (POM; variously also labeled OCM or OMC, and sometimes just called "organics") is now taken to be 

### 1.8 times that of the measured organic carbon (OC) concentration. (Confusingly, CALPOST labels the organics concentration as OC.)

The contribution of fine sea salt to light extinction has been added, and is accompanied by its own hygroscopic scattering enhancement factor, f,,(RH).

The light scattering by air itself (Rayleigh scattering) now varies with site elevation and mean temperature. It is to be rounded off to the nearest one ~m-' when used with the

new algorithm.

The light absorption by NO2 gas has been added.

The new IMPROVE algorithm is represented by the following formula:?

bar = 

### 2. 2fs(RH)*[small sulfate] 

## + 4.8f~(RH) *[large sulfate] +2. 4fs(RH) *[small nitrate] 

## + 5. I fL(RH)*[large nitrate] +2.8*[small organics] 

## + 6. 

### I *[large organics] 

## + 1 O*[elemental carbon] 

## + lofine soil] 

## + 1. 

### 7fss(RH)*[sea salt] +O. 6*[coarse matter] +Rayleigh scattering (site spec@) 

## +o. 33*[NO2(ppb)]



### The concentrations of "large" and "small" sulfate particles are calculated as follows:

[large suIfate] = 

### #otal surJnte]/20)*[total sulfate] if[total sulfate] < 

### 20 ,ug3

[large sulfate] = 

### [total sulfate] if[total sulfate] 

### 2 20 ,ugh3 

### (Eqs. 2)

[small sulfate] = 

### [total sulfate] - 

### [large sulfate].



### Identical formulas, with changes in component names, are used for nitrate and organics. In effect, these formulas conclude that low concentrations of these components are mainly in the form of "small" particles with their own extinction efficiency and fs(RH), while high

Square brackets denote concentrations.

### concentrations (approaching 20 &m3) are mainly in the form of "large" particles with a different extinction efficiency and fL(RH). The scaling factor [total sulfate]/20 sets the fraction of total sulfate that is small.

The sea salt concentration is taken to be 1.8*[Cl-] or, if chloride ion measurements are not available, the chlorine concentration can be used in its place. Site specific Rayleigh scattering values have been calculated for all IMPROVE sites.3 Nitrogen dioxide concentrations are not measured at IMPROVE sites, but the ambient NO2 concentrations under natural conditions can be expected to be negligibly small. The higher NO2 concentration in a source plume may be great enough to cause a change in visibility, however.

In order to enable CALPOST to calculate CALPUFF-modeled source impacts on visibility using the new IMPROVE algorithm, it would have to be extensively reprogrammed. As an alternative, such a calculation could be done "off line" by adding another layer of post processing after CALPOST. To this end, 

### I have developed a processor, in the form of an Excel workbook, that takes the CALPOST "Ranked Daily Visibility Change: Modeled Extinction by Species" output table, referenced against default annual average natural conditions concentrations, and creates an equivalent table of results based on the new algorithm. It can also incorporate the visibility impact due to light absorption by NO2 in the plume.

The following describes the science behind the processor (which we'll call the CALPOSTIMPROVE Processor) and provides instructions for using it.



### Concepts

In addition to the mechanical changes imposed by all the new terms in the new IMPROVE formula, applying the new algorithm also requires some conceptual changes. The biggest of these is that the extinction efficiencies of sulfates, nitrates, and organics now depend on the concentrations of those species. The practical implication of this is that extinction is no longer linearly additive. To calculate total extinction, you cannot take a background level of extinction and add to it CALPOST's calculation of extinction caused by the particulate matter coming from

a source, because when the two aerosols mix 

### in the atmosphere their combined mass concentration results in increases in the extinction efficiencies of both the background and the source contribution. This means that combining background particulate matter with the particulate matter from a source gives an extinction result that is greater than the sum of the two separate extinctions.

With the nonlinear behavior resulting from applying the new IMPROVE algorithm, the extinction impact of the source (i.e., the increase in extinction resulting from introducing source emissions into the atmosphere) is the sum of three parts:

I. The source impact calculated by the new IMPROVE algorithm using the CALPOST outputs for a plume in isolation;

Revised IMPROVE Algorithm for estimating Light Extinction from Particle Speciation Data. Report to IMPROVE Steering Committee, November 2005.

### 2. An increase in that source impact because the extinction efficiency increases when the source's aerosol combines with the background aerosol; and correspondingly,

3. 

### An 

### increase in the extinction of the background aerosol because of that same mixing.

The total new extinction is the sum of the above three components plus the original background extinction. The original background extinction is just that calculated by the new IMPROVE algorithm from background concentrations of the various components, without any consideration of the effects of the plume. For this application, the background is taken to be that described by EPA's default natural conditions. The difference between the total extinction and the background is the impact of the source.

More details about the calculation are given in the appendix.



### Description 

### of Processor

The CALPOST-LMPROVE Processor is a Microsoft Excel workbook that consists of four worksheets. In Version 2 the worksheets are the following.

1. Input & 

### Output - 

### The output table from CALPOST is imported to here and user entries are made for the Rayleigh scattering coefficient and, if desired, for a sea salt concentration at the Class I area of interest. The NO, concentration on each day attributable to the emissions from the source can also be entered together with an assumption of what fiaction of the NO, is in the form of NOz. A revised table, with extinction based on the new IMPROVE algorithm is then presented on the same page. This is the only page on which user input takes place, and the results of the calculations appear on this page.

2. Calculations 

## -- The calculations themselves are all done on this worksheet. There is no

user input to this page. The variables are explained on the worksheet itself, so the user can find intermediate values if so inclined.

3. 

### F(RH) - 

### This worksheet tabulates the traditional IMPROVE f(RH) against 

### RH, and then also lists values for the three new humidity growth functions, fs(FUI), ~L(RH), and fss(RH). It serves as a lookup table for the "Calculations" worksheet.

4. Rayleigh & 

### Sea Salt - 

### This page tabulates the IMPROVE-recommended Rayleigh scattering coefficients for all VISTAS Class I areas and for Class 

### I areas in adjacent states. It also lists the average sea salt concentrations for the same locations, as tabulated on the VIEWS web site, based on chloride or chlorine measurements by IMPROVE monitors between 2000 and 2004. This sheet just provides information for the user; it is

not linked to the rest of the workbook The user can obtain Rayleigh and sea salt numbers for the Class I area of interest fiom this table and then manually enter them in the designated spaces in worksheet 1.

### Instructions for Using the CALPOST-IMPROVE Processor

These instructions apply to Version 

### 2 of the processor. Version 

### 2 includes the ability to calculate the light extinction effects of NO2 resulting from the source's emissions.

Step 1. Begin by opening the output (.LST) file from a CALPOST visibility calculation 

### run in a text editor or word processing program.4 In the second half of the file, locate the table "Ranked Daily Visibility Change" with the subheading "Modeled Extinction by species".'

Step 2. Copy this table and paste it onto a new page. Save it as a text (.txt) file, not as a formatted (e.g., MS Word .doc or .rtf) file. The final table should contain only the column headings and the data. Delete all other captions, any additional data summaries at the end, and blank lines before

or after the table. The processor can handle a maximum of 

### 22 lines of data (i.e., the highest rank in the last, unlabeled, column should be 22) plus a row of column captions. Delete any data that exceed this limit. (Fewer than 

### 22 lines of data are OK.) The result should look like the example in Figure 1, although the line wrapping may differ.

Step 3. 

### Open the CALPOST-IMPROVE Processor in Microsoft Excel. Save the open file under a

new name so that the original empty processor will remain available for future use. The front worksheet, labeled "Input & 

### Output" looks like Figure 2. There is a large empty box, surrounded by double lines, into which the table created above will be imported, as described be10w.~ On the right is a box into which NO, concentrations may be entered manually, and a small box below this box is provided for entry of the user's assumption of what fraction of that NO, is in the form of NOz. Two smaller boxes provide for user input of the Rayleigh scattering coefficient and, optionally, sea salt concentration for the Class I area, as 

### described below. Results of the new IMPROVE algorithm calculations appear in blue in the lower half of the worksheet and some additional results, that are also useful for quality control, appear in green to the right of the large box. At the moment, many results cells will display nonsensical numbers and error messages, such as shown in Figure 2.

Step 4. Select the upper left cell (A7) in the large box. On the Excel menu bar, go to Data>Get External Data 

### and click on Import Text ~ile.' 

### (If the large box is not empty, click on Edit Text Import 

### instead.) Select the file that contains the table created in Step 

### 2 and click on the Get Data 

### button. Go through the Text Import Wizard steps, checking that all values appear correctly in separate columns. (The label "COORDINATES 

### (km)" will be split over two columns; this is OK.) When everything appears in order, click Finish.

4 The background concentrations that were entered into CALPOST must be the EPA-prescribed default annual average natural conditions concentrations for the East. The processor will not give correct answers if other concentrations were used in CALPOST.

For future reference in Step 

### 7, this may also be a good time to locate the table with the same title but with the subtitle "% of Modeled Extinction by Species", which appears later in the output file.

6 If the workbook 

### has already been used, the boxes may not be empty. This does not matter. 

# " The exact wording may vary slightly between different versions of Microsoft Excel. The terminology used here is from Excel 2004 for Macintosh.YEAR DAY HR RECEPTOR COORDINATES (km) TYPE BEXT(Mode1) BEXT(BKG) BEXT(Tota1) $CHANGE F(RA) bxSO4 bxN03 bxOC bxEC bxPMC bxPMF



### Figure 1. 

### Example of CALPOST Output Table, 

### in Proper Format for Importing into the CALPOST-IMPROVE Processor.

Step 5.* 

### The "Import Data" window will appear, with cell A7 indicated as the location at which data will be entered. Click on the Properties 

### button. In the window that appears, select "Overwrite existing cells with new data, clear unused cells" and uncheck "Adjust column width", then click on OK. Now click on the OK button in the "Import Data" window.

Step 

### 6. Assuming that your Excel application is set up to automatically recalculate whenever any entries are changed, you should now have filled the cells in the large box on the first worksheet,

If the processor already had data in it and 

### Edit Text Import was clicked in Step 4, then the "Import Data" window will not appear and Step 

### 5 can be skipped.

### numbers should have appeared in the green columns to the right, and some numbers will have appeared in the output table in blue on the lower half of the worksheet. If the data import worked properly, none of the imported data should have spilled out of the large box. Check that all the column captions in bold outside the large box are now duplicated

on the first line in the box. (There won't be a caption for Rank.)

Step 7. As a further check on whether everything is correct so far, the dv information in the three columns to the right of the large box should be the same as that in the second CALPOST table "Ranked Daily Visibility Change: % 

### of Modeled Extinction by Species", which was mentioned in Footnote 1.

Step 8. 

### Beneath the large box that was just filled with imported data, enter the Rayleigh scattering coefficient for the Class I area of interest into the top small box after red instruction 

### 3. Also, if you wish, fill in the other small box, the one after red instruction 4, 

### with the annual average sea salt concentration. (The sea salt box may be left blank, but the Rayleigh scattering coefficient box must be filled in.) To help with filling in these two boxes, the fourth worksheet, "Rayleigh & 

### Sea Salt", provides IMPROVE-calculated values of the Rayleigh coefficients for Class I areas in the VISTAS region and in adjacent states. Also, average sea salt concentrations for 2000-2004, calculated in accordance with the new IMPROVE procedures, can be found there.

Step 9.9 

### If the impact due to NO2 is to be considered, a second CALPOST run will be needed to provide the 24-hr average NOx concentrations estimated by CALPUFF. For this purpose, run CALPOST using the ASPEC = 

### NOX option in Input Group 1 of the CALPOST.INP control file. The NOx values to insert in the NO, input box on the Input & 

### Output page of the processor have to be extracted manually fiom the CALPOST output file for each date and receptor listed in the file that was imported in Steps 1 through 

### 5 above and are displayed in the left hand columns in the large box.

Step 10. Select a value between 0 and 1 to represent what fi-action of NOx is in the form of NO2. Enter this value into the small box at red instruction 

### 6 below the column where the NO, concentrations were entered.''

Step 11. The blue data table at the bottom of the page represents the new IMPROVE algorithm outputs. An 

### example is shown in Figure 

### 3. This table can be compared with the original CALPOST table at the top of the page. All of the columns in both tables show exactly the same variables, except that the F(RH) column in the top table is replaced by just the RH in the lower table (since the new procedure has three different f(RH) functions) and a new baNO2 column has been added to the bottom table to show the light absorption due to NO2 (in ~m-'). Although the events are listed in the same order in both tables, note that their rankings may have changed, as is the case for many of the lines in the blue output table in Figure 3.

9 Steps 8 and 9 are optional. If the impact due to NO2 is not of interest, just leave the entry fields mentioned in these steps blank.

10 An easy way to see the effect of the NO? on the source's impact in the output table in the lower half of the page is to toggle this NOJNO, value between the selected value and zero.

### For those who are interested in more detail concerning the calculations that take place, values of the three f(RH) functions appear in columns 

### M through 0 

### on the second, "Calculations" spreadsheet. The extinction impact of the source, including enhancement of the extinction efficiencies for sulfates, nitrates, and organics because of greater total

mass concentrations, appears in columns V through AC. Extinction due to the annual average natural background appears in Columns AJ through AN; natural background extinctions for those components that are enhanced by greater total mass concentrations

appear in columns AU through AX.

## Appendix Details of Calculation Approach

As 

### an example of the calculation steps, assume that the sulfate concentration resulting from emissions from a source is [SE] and the sulfate in the undisturbed natural background is [SN], for a total ambient sulfate concentration of [ST]. According to Equations 1 and 2 in the main body of this document, the total extinction due to sulfate for this combination is

bat(sulfate) = 

### 2.2f~(RH)*[srnall sulfate]+ 4.8.fL(RH) 

### *[large sulfate], (Eq. A-1)

where

[large sulfate?-] = 

### [ST] if[S~] 

### L 20 ,ug/m3 (Eqs. A-2)

[small 

### sulfate^] = 

### [ST] - 

### [large 

### sulfate^],

and the subscript 

### T denotes total sulfate

For the original background, where there is no source impact, the corresponding formulas for the terms in Equations A-2 are

(Eqs. A-3)



### [small sulfateN] = 

### [SN] - 

### [large sulfateN],

where the subscript N denotes natural sulfate.

Similar calculations need to be carried out for nitrates. Contributions of the other particulate components are linear and can just be calculated according to Equation 

### I.

If the impact due to NO2 is also to be considered, then the source impact due to this component is, according to Equation 1,

where EN021 

### is in ppb. It is reasonable to assume that the ambient NO2 concentrations under natural conditions would be so small as to cause negligible light absorption, so the corresponding term is not needed 

### in the natural conditions calculation.

The contributions due to the various components are summed together as in Equation 1 to obtain the total extinction bext,T and the natural background extinction bexfN. The

### fractional change in extinction is then calculated as the difference, normalized by 

### the natural background extinction

a result that can also be expressed in deciviews.

These formulas are used in the CALPOST-IMPROVE Processor. Similar formulas apply for nitrates and organics. There is no nonlinearity in the remaining terms in Equation 1."Rogers, Tom" To Brenda JohnsonlR4/USEPAIUS@EPA cTom.Rogers@dep.state.fl.us

> CC

01/11/2008 11:31 AM bcc Subject RE: Spreadsheet for new IMPROVE equation request

Histiny: 

### 43 This 

### message has been replied to,

Brenda, The spreadsheet is attached. It's the one that Dr. Ivar Tombach produced for VISTAS that includes the NO2 term.

Let me know 

### if you need anything else. Tom

Tom Rogers Division of Air Resource Management Florida Department of Environmental Protection f850) 921-9554

Please note: Florida has a very broad public records law. Most written communications to or from state officials regarding state business are public records available to the public and media upon request. Your e-mail communication may therefore be subject to public disclosure.

The Department of Environmental Protection values your feedback as a customer. DEP Secretary Michael W. Sole is committed to continuously assessing and improving the level and quality of services provided to you. Please take a few minutes to comment on the quality of service you received. Simply click on this link to the DEP Customer Survey



### . Thank you in advance for completing the survey. From: Johnson.Brenda@epamail.epa.gov [mailto:Johnson.Brenda@epamail.epa.gov] Sent: Friday, January 11, 2008 1l:lO AM To: Rogers, Tom Subject: Spreadsheet for new IMPROVE equation request

Hello Tom, I need you to send me a copy of the spreadsheet that is being used to implement the new IMPROVE equation in the Florida BART applications. This is a part of the documentation to support your January 3, 2008 letter to our Regional Administrator.

Take care and have a great day!

Brenda C. Johnson Air Planning Branch US EPA Region 4 Atlanta. GACALPOST-IMPROVE ProcessorfortheEastREVISEDDRAFT2August2006CALPOSTRecalculationwithNewIMPROVE Algorithm............................INPUTfromCALPOST(basedon old IMPROVE algorithm)----------I.AtcellA7,Import "Ranked DallyV~sibilityChange"(bext)table,includingcolumnhead~ngs,fromCALPOST(22days,max)YEARDAYHRRECEPTORCOORDINATES(km)TYPEBEXT(Mode1)BEXT(BKGBEXT(Tota1)%CHANGEF(RH)bxM4bxNO3bxOCbxECbxPMCbxPMFRank3.Enter value ofsite-specificRayleighscattermgcoefficient,from"RayleighPSeaSalt"worksheet4.(Optional)Insertannualaverageseasaltconcentratlon,from"Rayleigh&SeaSalt"wo*sheet.Leaveblankit notused,8.e.defaultis0.I3..................................OUTPUT(basedonnewIMPROVE algorithm)------------------------.5.Checkcalculated values(Opttonal)belowagalnstCALPOST'sEnter24hr"RankedDaitvVisibilltvNOxconc.6.EnterdeswedN02/NOxratio (default is0)uNewYEARDAYHRRECEPTORCOORDINATES(km)TYPEBEXT(SourccBEXT(BK6BEXT(Tota1)%CHANG=@b604bpNO3hOCbsECbsPMCWMFbaNO2Rankdv(total)0000000#N/A+N/A#N/A#N/A#N/A#N/A#N/A000001#N/A0000000#N/APN/A#N/A#N/A#N/A#N/A#N/A0 00001*N/A00000 00*N/A#N/A+N/A#N/ABN/A#N/APN/A000001#N/A0000000#N/APN/A#N/A#N/A#N/A#N/AKN/A000001#N/A0000000#NlA#N/A#N/A#N/A#N/A*N/A#N/A000001#N/A0000000#N/A#N/A#N/A#N/A#N/A#N/A#N/A0000 01tN/A00000 00#N/A#N/A#N/AkNIA#N/A#N/AtN/A000001#NIA0000000#N/A#N/A#N/A#N/A#N/A#N/A#N/A000001#N/A0000000#N/A#N/A#N/A#N/A#N/A#N/A#N/A000001#N/A000000 0#N/A#N/A#N/A#N/A#N/A#N/A#N/A000001#N/A0000000#N/A#N/A#N/AtN/A#N/A#N/A+N/A000001#N/A0000000#N/A#N/A#N/AaN/A#N/A#N/A#N/A000001tN/A0000000#N/A#N/A#N/A#N/A#N/A#N/A#N/A000001#NIA0000000#N/A#N/A#N/A#N/A?N/A#N/A#N/A000001PNIA00000 00BNIA#N/A#N/A#N/A#N/A#N/APNIA000001#N/A0000000#N/AtN/A#NJAPN/A#N/A#N/AKN/A000001#NIA0000000#N/A#N/A#N/ASN/A#N/A#N/A#N/A000001PN/A0000000#N/A#N/A#N/A#N/A#N/ABNIA#N/A000001?NJA00000 0 01NIA#N/A8NIAkN/A#N/A#N/AdN/A00 0 001#NIA00000 0 0#N/A+N/A#N/AKN/A#N/A#N/AaN/A000001#N/A0000000#N/A#N/A#N/ARN/A#N/A#N/A#N/A0000 01#N/A00000 0 0#N/A#N/A#N/A#N/A#N/A#N/A#N/A000001#N/AAdv0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000000.00*- -.-0000000000000000000000 ~u0000000000000000000000 yoOOOOOOOOOOOOOOOOOOOOOO ~EOOOOOOOOOOOOOOOOOOOOOO 

## ~jooooooooooOooOOoOOoooo

~;,,,,,,,,,oooooooao,,,, ao\.\\\\\\\..\\\\.\\\\\\ 22>>>>>>>>>>>>>>>>>>>> ~~onZZZZEZEEEEEZZZZZZZZ~

0~###################### w- rm-. -. -. -. -. -. -. -. -. -. oo?????????????????????? cz2222222222222222222222 ~Eooanooonaooanoa~nnnnnn OW#########*############ 

### 55,,,,,,,,,,,,,,,o,ooooo ,,,,,,,,,,\\.,,,,,,,,, ~22222222222222222222222 ~mannnnnnnanannnnnannaaa

....................... 

## .B Waoooo,,,,,z,,,,,,,,o,,o



### =:

:23333333333333333333333 lEZZZZZZZZZZEEEEEZZZZZZE ,',W######################NNNN aaaa 4rldd 0000

mmmm mmmm 

## u??::

-. -. -, -. ???? 2222 nnna ##*#

-. -. -. -. 0000 

## 5-5-22

n n n 0 ####

-. -. -, -. ???? 2222 noon #### NNNNNNNNNNNNN awawwwaaawwaw +dddd.+dddd44.-, 0000000000000

mmmmmmmmmmmmm mmmmmmmmmmmmm

### Old 

### and New F(RH) 

### Values Old F(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.02 1.04 1.06 1 .08

1.1 1.13 1.15 1.18

1.2 1.23 1.26 1.28 1.31 New Fs(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.38

1.4 1.42 1.44 1.46 1.48 1.49 1.51 1.53 1.55 1.57 1.59 1.62 New FI(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.31 1.32 1.34 1.35 1.36 1.38 1.39 1.41 1.42 1.44 1.45 1.47 1.49 New Fss(RH) 

### 1 1 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2.36 2.38 2.42

### Salt concentratibnsfor Class I Areas of VISTAS and Nearby States 

# *

Class I 

### Area

VISTAS States Cape Romain W Chassahowitzka W Cohutta W Dolly Sods W Everglades NP Great Smoky Mtns. NP James River Face W. Linville Gorge Mammoth Cave NP Okefenokee W Otter Creek W St. Marks W. Shenandoah NP Shining Rock W Sipsey W Swanquarter W Wolf Island W. Wolf Island W.**

Nearby States Breton W Brigantine W Caney Creek Hercules-Glades Mingo W Upper Buffalo W State

SC FL G A 

## wv FL TN VA NC KY GA WV FL VA NC AL NC GA GA

LA 

### NJ AR MO MO AR Sea Salt IMPROVE 

### lJg/m3 Monitor

Unknown 0.22 0.03 0.04 0.01 0.03 OKEFl ROMAl



## * Rayleigh scattering values for the relevant IMPROVE monitor are from the IMPROVE memo about the revised algorithm. Sea salt concentrations are averages for 2000-2004 based on data from the VIEWS web site. 

## ** Alternative values for Wolf Island based on Cape Romain measurements. Being at sea level and on the coast, Cape Romain values may be more representative of Rayleigh and sea salt conditions at Wolf island than those at Okefenokee, which is above sea level and far from the shore.

### Why Use the 

### New 

### IMPROVE Algorithm?

The new IMPROVE algorithm, which has been approved by the IMPROVE Steering Committee, is a much better representation of the effects of particulate matter on light extinction than the old IMPROVE algorithm. Excellent justification of this conclusion is provided in the November 2005 report of the IMPROVE Steering Committee, "Revised IMPROVE Algorithm for Estimating Light Extinction from Particle Speciation Data"

The new algorithm incorporates changes that represent much of what has been learned about the relationship between particulate matter component concentrations and light extinction in the more than a decade since the oId algorithm was developed. The main reasons that justify using the new algorithm instead of the old one are the following:

1. The new algorithm overcomes the biases of the old algorithm on the haziest days (when the old algorithm underestimates light extirictionj and on the clearest days (when the old algorithm overestimates extinction). This improvement can be seen by comparing measured Iight extinction from nephelometers with light extinction calculated using either the original IMPROVE equation or the new IMPROVE equation. Figures 1,2, and 3 in this summary illustrate the performance of the

new and old equations compared to nephelometer data for Great Smoky Mountains and Shenandoah National Parks and Cape Romain Wildlife Refuge. Additional examples are available in figures and the appendix of the IMPROVE report referenced above and on the Air Resource Specialists Rp site (ftp://fkp.airresource.comNISTAS/4c~Neph~Compare/.)

2. The new algorithm recognizes that Iight extinction efficiencies vary from location

to location and time to time as the size distribution of the aerosol changes, and it reflects this variation by increasing the extinction efficiency as the concentrations of sulfates, nitrates, and organics increase. It also recognizes that the humidityrelated growth rates of particles differ depending on their sizes. As a result, the

new algorithm generally does a better job of representing light extinction at individual sites than does the old algorithm, as indicated by the reduced fractional biases in each RPO region shown in Tables 3 and 5 (versus Tables 2 and 4) from the report mentioned above and copied into this summary.

3. The new algorithm recognizes research findings that show that fine sea salt can be

an important contributor to light extinction in coastal areas, and thus includes a

new term that reflects its contribution and its hygroscopic growth with increasing relative humidity. The old algorithm ignores sea salt, probably because it was originally developed mainly for inland Class I areas in the inter-mountain West (although incorporating sea salt into the calculation was already considered in a University of California at Davis memo in 1995).

### The new algorithm acknowledges that substantial recent research has shown that the mass concentration of particulate organic matter (often denoted by 

### OMC in IMPROVE publications) in rural areas is a greater multiple of the measured OC concentration than the 1.4 value used 

### in the old algorithm. The new algorithm updates the factor to a more-appropriate1.8.

The new algorithm recognizes that there may be times (near urban areas or in

some source emission plumes) when light absorption by 

### NOz gas is a meaningful contributor to light extinction, and thus includes a new term based on the NO2 concentration.

The new algorithm recognizes that 

### the assumption of constant Rayleigh scattering of 10 

### ~m" (representative of an elevation of about 5000 feet) may have been adequate when only inter-mountain West sites were considered, but is a distortion for sites close to sea level or with very hot or cold climates. It thus allows for sitespecific values of the Rayleigh scattering.

At any given location, the net result of all these changes is typically small 

### on average because some changes result in increases in extinction and some in decreases, but the apportionment of that extinction to the various components is more accurate with the new algorithm, especially on the haziest and clearest days. This is particularly important for the development of emission management strategies. because the benefits of control of concentrations of each species will be represented more correctly with the new algorithm.

Figure I. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old 

### IMPROVE Algorithm and Daily f(RH), Great Smoky Mountains National Park, 1995-

. .. - 

### New IMPROVE Old IMPROVEFigure 2. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old 1MPROVE Algorithm and Daily f(RH), Shenandoah National Park, 1996-2004.

New IMPROVE Old IMPROVE

Figure 3. Aerosol Scattering vs Nephelometer Scattering Comparing New and Old IMPROVE Algorithm and Daily f(RH), Cape Romain Wildlife Refuge, 2004.

New IMPROVE Old IMPROVEThe Tables below were copied from the report "Revised IMPROVE Algorithm 

### for Estimating Light Extinction from Particle Speciation Data" available 

### from the VIEWS website.

Table 2. Averaged fractional bias by 

### RPO for the current 

### IMPROVE algorithm with quintiles based 

### on measured light scattering (criterion 1). Bold font highlights the bias values that are lower than corresponding values in Table 3.

RF'O Quintiie 1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.67 0.18 0.10 0.02 -0.1 1 0.17 MANE 0.93 0.27 0.19 0.10 0.01 0.28 VISTAS 0.59 0.21 0.1 1 0.02 -0.13 0.16 WRAP 1 .07 0.37 0.18 0.07 -0.08 0.32

Table 

### 3. Averaged fractional bias 

### by RPO for the current new proposed algorithm with quintiles based on measured light scattering (criterion 1). Bold font highlights the bias values that are lower than corresponding values in Table 2.

RPO Quintile I Quintile 2 Quintile 3 Quintile 4 Quintiie 5 Average CEN 0.51 0.08 0.02 -0.03 -0.08 0.10 MANE 0.74 0.14 0.06 0.01 -0.02 0.17 VISTAS 0.50 0.16 0.1 1 0.06 -0.01 0.16 WRAP 0.84 0.25 0.08 0.01 -0.10 0.21

Table 4, Averaged fractional bias by 

### RPO for the current 

### IMPROVE algorithm with quintiles based on estimated light scattering (criterion 2). Bold font highlights the bias values that are lower than corresponding values in Table 

### 5.

RPO Quintile 1 Quintile Z Quintile 3 Quintile 4 Quintile 5 Average CEN 0.42 0.19 0.1 8 0.09 -0.01 0.17 MANE 0.35 0.27 0.30 0.33 0.15 0.28 VISTAS 0.38 0.19 0.14 0.08 0.01 0.16 WRAP 0.58 0.37 0.26 0.25 0.15 0.32

Table 5. Averaged fractional bias by 

### RPO for the current new proposed algorithm with quintiles based on estimated light scattering (criterion 2). Bold font highlights the bias values that are lower than corresponding values in Table 4,

RPO Quintile 1 Quintile 2 Quintile 3 Quintile 4 Quintile 5 Average CEN 0.23 0.1 1 0.08 0.06 0.02 0.10
MANE 0.15 0.14 0.15 0.19 0.21 0.17 VISTAS 0.25 0.14 0.08 0.13 0.21 0.16 WRAP 0.37 0.19 0.19 0.16 0.17 0.31

## Ivar Tombach, Ph. D.

8&rn>Wd %fldY 753 Grada Ave. Camarilla, CA 9301 0 805 388-2341 805 445-9424 fa itombach@aol.com



## Instructions: A 

## Postprocessor for Recalculating CALPOST Visibility Outputs with the New IMPROVE Algorithm

Version 2 14 October 

### 2006

Introduction

CALPOST can be used to processes outputs from CALPUFF modeling of a source's emissions to calculate the 24-hr average visibility impairments caused by primary and secondary particulate matter attributable to emissions from the modeled source. Those increments are presented in two tables, both labeled "Ranked Daily Visibility Change", in the CALPOST output (.LST) file. The table of interest to us has the subtitle "Modeled Extinction by Species" and lists the dates and locations of such incremental impacts in light extinction (bext) in ranked order, starting with the one that represents the largest percentage change in light extinction.'

In addition, with a different setup of the control file CALPOST.INP, the CALPOST postprocessor can be used to calculate 24-hr averages of NOx concentrations. As described below, the outputs from that additional CALPOST 

### run can be used to assess the visibility impact of the NO2 gas 

### in the source plume.

Visibility effects due to particulate matter are calculated in CALPOST from CALPUFF-modeled particulate matter component concentrations using effectively the "traditional" IMPROVE algorithm. CALPOST allows for choice of the humidity scattering enhancement function (f(RH))

to be used with the IMPROVE algorithm; for modeling in connection with the US EPA's Regional Haze Regulations (RHR), the appropriate form of f(RH) is the one described and tabulated in the EPA's 2003 guidance for tracking progress under the RHR. Visibility effects due

to NO2 are not considered in the CALPOST visibility calculation.

Recently, the IMPROVE Steering Committee developed a new algorithm for estimating light extinction from particulate matter component concentrations. This algorithm (the "new IMPROVE algorithm) provides a better correspondence between the measured visibility and

1 The other table in the CALPOST visibility output file, with the subtitle "% of Modeled Extinction by Species", provides equivalent results in terms of changes in the haze index, in deciviews. The two tables represent the same results, with identical ranking of events, while just using different (but mathematically related) metrics.

### that calculated from particulate matter component concentrations. The new algorithm differs in several substantive ways from the traditional one:

The extinction efficiencies of sulfates, nitrates, and organics have been changed and are

now functions of their concentrations. The extinction efficiencies of sulfate and nitrate

are no longer identical, although the new hygroscopic scattering enhancement factors applied to them are the same.

The concentration of particulate organic matter (POM; variously also labeled OCM or OMC, and sometimes just called "organics") is now taken to be 1.8 

### times that of the measured organic carbon (OC) concentration. (Confusingly, CALPOST labels the organics concentration as OC.)

The contribution of fine sea salt to light extinction has been added, and is accompanied by its own hygroscopic scattering enhancement factor, f,,(RH).

The light scattering by air itself (Rayleigh scattering) now varies with site elevation and

mean temperature. It is to be rounded off to the nearest one ~m-' when used with the

new algorithm.

The light absorption by NO2 gas has been added.

The new IMPROVE algorithm is represented by the following f~rmula:~

bar = 

### 2.2fs(RH)*[small sulfate] 

### + 4.8f~(RH)*[large sulfate] +2. 4fs(RH)*[smal nitrate] 

## + 5. I .fL(RH)*[large nitrate] +2.8*[small organics] 

## + 6. 

### I *[large organics] +I O*[elemental carbon] +I *@ne soil] +I. 7.fs(RH)*[sea salt] +O. 6*[coarse matter] +Rayleigh scattering (site spec&) +0.33*[N02@pb)l



### The concentrations of "large" and "small" sulfate particles are calculated as follows:

[large sulfate] = 

### {[total sulfateJ/20]*[total sulfate] $[total sulfate] < 

### 20 ,ug3

[large sulfate] = 

### [total sulfate] if[total sulfate] 

## L 20 

### ,ugh3 (Eqs. 2)

[small sulfate] = 

### [total sulfate] - 

### [large sulfate].



### Identical formulas, with changes in component names, are used for nitrate and organics. In effect, these formulas conclude that low concentrations of these components are mainly in the form of "small" particles with their own extinction efficiency and fs(RH), while high

2 Square brackets denote concentrations.

### concentrations (approaching 20 pg/m3) are mainly in the form of "large" particles with a different extinction efficiency and fL(RH). The scaling factor [total sulfate]/20 sets the fraction of total sulfate that is small.

The sea salt concentration is taken to be 1.8*[C1-] or, if chloride ion measurements are not available, the chlorine concentration can be used in its place. Site specific Rayleigh scattering values have been calculated for all IMPROVE sites.3 Nitrogen dioxide concentrations are not measured at IMPROVE sites, but the ambient NO2 concentrations under natural conditions can be expected to be negligibly small. The higher NO2 concentration in a source plume may be great enough to cause a change in visibility, however.

In order to enable CALPOST to calculate CALPUFF-modeled source impacts on visibility using the new IMPROVE algorithm, it would have to be extensively reprogrammed. As an alternative, such a calculation could be done "off line" by adding another layer of post processing after CALPOST. To this end, I have developed a processor, in the form of an Excel workbook, that takes the CALPOST "Ranked Daily Visibility Change: Modeled Extinction by Species" output table, referenced against default annual average natural conditions concentrations, and creates an equivalent table of results based on the new algorithm. It can also incorporate the visibility impact due to light absorption by NO2 in the plume.

,The following describes the science behind the processor (which we'll call the CALPOSTIMPROVE Processor) and provides instructions for using it.



### Concepts

In addition to the mechanical changes imposed by all the new terms in the new IMPROVE formula, applying the new algorithm also requires some conceptual changes. The biggest of these is that the extinction efficiencies of sulfates, nitrates, and organics now depend on the concentrations of those species. The practical implication of this is that extinction is no longer linearly additive. To calculate total extinction, you cannot take a background level of extinction and add to it CALPOST7s calculation of extinction caused by the particulate matter coming from a source, because when the two aerosols mix in the atmosphere their combined mass concentration results in increases in the extinction efficiencies of both the background and the source contribution. This means that combining background particulate matter with the particulate matter from a source gives an extinction result that is greater than the sum of the two separate extinctions.

With the nonlinear behavior resulting from applying the new IMPROVE algorithm, the extinction impact of the source (i.e., the increase in extinction resulting from introducing source emissions into the atmosphere) is the sum of three parts:

1. The source impact calculated by the new IMPROVE algorithm using the CALPOST outputs for a plume in isolation;

Revised IMPROVE Algorithm for estimating Light Extinction from Particle Speciation Data. Report to IMPROVE Steering Committee, November 

### 2005.



### 3

### 2. An increase in that source impact because the extinction efficiency increases when the source's aerosol combines with the background aerosol; and correspondingly,



### 3. An 

### increase in the extinction of the background aerosol because of that same mixing.

The total new extinction is the sum of the above three components plus the original background extinction. The original background extinction is just that calculated by the new IMPROVE algorithm fiom background concentrations of the various components, without any consideration of the effects of the plume. For this application, the background is taken to be that described by EPA's default natural conditions. The difference between the total extinction and the background is the impact of the source.

More details about the calculation are given in the appendix.

Description of Processor

The CALPOST-IMPROVE Processor is a Microsoft Excel workbook that consists of four worksheets. In Version 2 the worksheets are the following.

Input & 

### Output - 

### The output table from CALPOST is imported to here and user entries

are made for the Rayleigh scattering coefficient and, if desired, for a sea salt concentration at the Class I area of interest. The NO, concentration on each day attributable to the emissions from the source can also be entered together with an assumption of what fraction of the NO, is 

### in the form of NO2. A revised table, with extinction based on the new IMPROVE algorithm is then presented on the same page. This is the only page on which user input takes place, and the results of the calculations appear on this page.

Calculations 

## -- The calculations themselves are all done on this worksheet. There is no

user input to this page. The variables are explained on the worksheet itself, so the user can find intermediate values if so inclined.



### F(RH) - 

### This worksheet tabulates the traditional IMPROVE f(RH) against RH, and then also lists values for the three new humidity growth functions, fs(RH), fL(RH), and fss(RH). It serves as a lookup table for the "Calculations" worksheet.

Rayleigh & 

### Sea Salt - 

### This page tabulates the IMPROVE-recommended Rayleigh scattering coefficients for all VISTAS Class I areas and for Class I areas in adjacent states. It also lists the average sea salt concentrations for the same locations, as tabulated

on the VIEWS web site, based on chloride or chlorine measurements by IMPROVE monitors between 2000 and 2004. This sheet just provides information for the user; it is

not linked to the rest of the workbook. The user can obtain Rayleigh and sea salt numbers for the Class 

### I area of interest fiom this table and then manually enter them in the designated spaces in worksheet 1.

### Instructions for 

### Using the CALPOST-IMPROVE Processor

These instructions apply to Version 2 of the processor. Version 

### 2 includes the ability to calculate the light extinction effects of NO2 resulting from the source's emissions.

Step 1. Begin by opening the output (.LST) file from a CALPOST visibility calculation run in a text editor or word processing program.4 In the second half of the file, locate the table "Ranked Daily Visibility Change" with the subheading "Modeled Extinction by ~~ecies".~

Step 2. Copy this table and paste it onto a new page. Save it as a text (.kt) file, not as a formatted (e.g., MS Word .doc or .rtf) file. The final table should contain only the column headings and the data. Delete all other captions, any additional data summaries at the end, and blank lines before or after the table. The processor can handle a maximum of 22 lines of data (i.e., the highest rank 

### in the last, unlabeled, column should be 22) plus a row of column captions. Delete any data that exceed this limit. (Fewer than 22 lines of data are OK.) The result should look like the example in Figure 1, although the line wrapping may differ.

Step 3. 

### Open the CALPOST-IMPROVE Processor in Microsoft Excel. Save the open file under a

new name so that the original empty processor will remain available for future use. The front worksheet, labeled "Input & 

### Output" looks like Figure 2. There is a large empty box, surrounded by double lines, into which the table created above will be imported, as described be10w.~ On the right is a box into which NO, concentrations may be entered manually, and a small box below this box is provided for entry of the user's assumption of what fraction of that NOs is in the form of NOz. Two smaller boxes provide for user input of the Rayleigh scattering coefficient and, optionally, sea salt concentration for the Class I area, as described below. Results of the new IMPROVE algorithm calculations appear in blue 

### in the lower half of the worksheet and some additional results, that are also useful for quality control, appear in green to the right of the large box. At the moment, many results cells will display nonsensical numbers and error messages, such as shown in Figure 2.

Step 4. Select the upper left cell (A7) in the large box. On the Excel menu bar, go to 

### Data>Get External Data and click on 

### Import Text ~ile.' (If the large box is not empty, click on 

### Edit Text Import instead.) Select the file that contains the table created in Step 2 and click on the 

### Get Data button. Go through the Text Import Wizard steps, checking that all values appear correctly in separate columns. (The label "COORDINATES 

### (km)" will be split over two columns; this is OK.) When everything appears in order, click 

### Finish.

The background concentrations that were entered into CALPOST must be the EPA-prescribed default annual average natural conditions concentrations for the East. The processor will not give correct answers if other concentrations were used in CALPOST.

For future reference in Step 

### 7, this may also be a good time to locate the table with the same title but with the subtitle "% of Modeled Extinction by Species", which appears later in the output file.

If the workbook has already been used, the boxes may not be empty. This does not matter. 

# ' The exact wording may vary slightly between different versions of Microsoft Excel. The terminology used here is fiom Excel 2004 for Macintosh.YEAR DAY FIR RECEPTOR COORDINATES (km) TYPE BEXT(Mode1) BEXT(BKG) BEXT(Tota1) %CHANGE F(RH) bxSO4 bxN03 bxOC bxEC bxPMC bxPMF 21.650



### Figure 1. Example of CALPOST Output Table, 

### in Proper Format for Importing into the CALPOST-IMPROVE Processor.

Step 5.8 

### The "Import Data" window will appear, with cell A7 indicated as the location at which data will be entered. Click on the Properties 

### button. In the window that appears, select "Overwrite existing cells with new data, clear unused cells" and uncheck "Adjust column width", then click on 

### OK. Now click on the 

### OK button in the "Import Data" window.

Step 6. 

### Assuming that your Excel application is set up to automatically recalculate whenever any entries are changed, you should now have filled the cells in the large box on the first worksheet,

If the processor already had data in it and 

### Edit Text Import 

### was clicked in Step 4, then the "Import Data" window will not appear and Step 

### 5 can be skipped.1.AtcettA7,import"RankedDailyVtsibilttyChange"(bext)table,tncludtnpcolumnheadings,fromCALPOST(22days,rnax)3.tntrivalwofsite-s~rclliiRavIe,rrhscattertriocoetfmentfrom"Ravlstilh&Sea5eW'2.Checkceiculalrdvaluesbelow5.(Oyt$onnl)sgainrtCALPOST',"RankedOnilyEnter24hrVm~bilttyCharlge'(dv)tableNOicotic.NONPPb)RNUM'PNUM''#NUM'kNUM,'nNUM''iiNUM8~NvM''#NUM''IINIaM6.EnterdeswudNU2/NOxratlo(defaultIS0)....... .....NewYEARPAY,!if4PECEPTORCOORDINATES(km)NPE~U(T(Sourcs)~~(BKG),BfXT(To~l),%CHANGEjFHl%).:b.+04bsN03brOCbrECbsPMCblPMFbaNO2Rankdv(total)dv(bk9)'0000'$Or0*N/A#N/AINIAIIN/A$N/A'pN/A'*N/A000001'*N/A'#N/hOr0'0'0'0'0'IN/A'#N/A'#N/A'#N/ArrN/A'IN/A'aN/A00 0001'lN/A*#N/A*0'0'0'0'0'0'0'#N/A'tN/A'4NIA'#N/A'rN/A'#N/A'#N/A000001'#N/A'4N/A'0'0.0'0'0' 0'0'nN/A'rN/A'ZNIA'tN/A'4NIA'#N/A'CNIA000001'BNIA'*N/A'0'0'0'Or0'0'OrbN/A'#N/A'CNIA'INIA'#N/A'tN/A'*N/A000001'ltNIA'*NlA'0' 0'0'0'0'0.0'tNIA'#N/A'#N/A'L'NIA'PN/A'flNIA'*N/A000001'*N/A#N/A0'0'0'0'0'0'0'#M/A'#N/A'#N/AXNfA'RNIA'PNIA'4NIA000001'bN/A'tiNIA0'0'0'0'0'0'0'#MIA'#N/A'INfA'#N/A'rNIA'IN!A'#N/A00O00I'*N/A'UNIA0'0'0'0'0'0'0'4N/A'fNIA'IN/A'4N/A'aN/Ar*N/A*N/A000001'XN/A'BNIA'0'0'0'0'0'0'Or#N/A'#N/A'#N/A'IIN/A'CNIA'rN/A'%lN/A000001'rN/A'lN/A'0'0'0'0'0' 0'0'flNIA'#N/A'#N/A'#N/A'#N/ArnN/A'#N/A000001'4NlA'IINIAIINIA''#./A'PNIA''FN/d'RNIAbNIA#N/A#N/h#N/AINIA#NIAtlN/A#N/AItNIA'#N/A'4NIA'*N!A'4N/A'*N/A'*N/A'4N/A*N/APNIA.fNfA'*N/A'*N/A'4N/A'*N/A'#N/A'PNIA'tN/A'*N/A*N/A'#N/AAdv0.000.000.000000000.000000.000.000.000.00Figure2.Example of Appearance of Input&Output Worksheet before Data Entry.

### numbers should have appeared in 

### the green columns to the right, and some numbers will have appeared in the output table in blue on the lower half of the worksheet. If the data import worked properly, none of the imported data should have spilled out of the large box. Check that all the column captions in 

### bold outside the large box are now duplicated on the fxst line in the box. (There won't be a caption for Rank.)

Step 7. As a further check on whether everything is correct so far, the dv information in the three columns to the right of the large box should be the same as that in the second CALPOST table "Ranked Daily Visibility Change: % 

### of Modeled Extinction by Species", which was mentioned in Footnote 1.

Step 

### 8. Beneath the large box that was just filled with imported data, enter the Rayleigh scattering coefficient for the Class I area of interest into the top small box after red instruction 3. 

### Also, if you wish, fill in the other small box, the one after red instruction 4, with the annual average sea salt concentration. (The sea salt box may be left blank, but the Rayleigh scattering coefficient box must be filled in.) To help with filling in these two boxes, the fourth worksheet, "Rayleigh & 

### Sea Salt", provides IMPROVE-calculated values of the Rayleigh coefficients for Class I areas in the VISTAS region and in adjacent states. Also, average sea salt concentrations for 2000-2004, calculated in accordance with the new IMPROVE procedures, can be found there.

Step 

### 9.9 If the impact due to NO2 is to be considered, a second CALPOST run will be needed to provide the 24-hr average NO, concentrations estimated by CALPUFF. For this purpose, run CALPOST using the ASPEC = 

### NOX option in Input Group 1 of the CALPOST.1NP control file. The NO, values to insert 

### in the NO, input box on the Input & 

### Output page of the processor have to be extracted manually £rom the CALPOST output file for each date and receptor listed in the file that was imported in Steps 1 through 5 above and are displayed in the left hand columns in the large box.

Step 10. Select a value between 0 and 

### 1 to represent what fiaction of NO, is in the form of NOz. Enter this value into the small b~x at red instruction 

### 6 below the column where the NO, concentrations were entered."

Step 11. The blue data table at the bottom of the page represents the new IMPROVE algorithm outputs. An example is shown in Figure 

### 3. This table can be compared with the original CALPOST table at the top of the page. All of the columns in both tables show exactly the same variables, except that the F(RH) column in the top table is replaced by just the 

### RH in the lower table (since the new procedure has three different 

### f(RH) functions) and a new baNOz column has been added to the bottom table to show the light absorption due to NO2 (in ~rn-I). Although the events are listed in the same order in both tables, note that their rankings may have changed, as is the case for many of the lines in the blue output table in Figure 

### 3.

Steps 8 and 9 are optional. If the impact due to NO2 is not of interest, just leave the entry fields mentioned in these steps blank.

10 An easy way to see the effect of the NOz on the source's impact in the output table in the lower half of the page is to toggle this N02/N0, value between the selected value and zero.

### For those who are interested in more detail concerning the calculations that take place, values of the three f(RH) functions appear in columns 

### M through 

### 0 on the second, "Calculations" spreadsheet. The extinction impact of the source, including enhancement of the extinction efficiencies for sulfates, nitrates, and organics because of greater total

mass concentrations, appears in columns V through 

### AC. Extinction due to the annual average natural background appears in Columns AJ through 

### AN; natural background extinctions for those components that are enhanced by greater total mass concentrations

appear 

### in columns 

### AU through 

### AX.CALPOSTRecalculatlonwithNewIMPROVEAlgorithm............................INPUTfromCALPOST(basedonold IMPROVE algorithm)....................I.AtcellA7,import"RankedDallyVisth~lityChange"(bcxt)table,~ncludingcolumnheadings,fromCALPOST(22days,mnx)2002175010271479.06924.683D2002 172010211479.24423.778D2002 284 010451484.348 27.58D2002 3530 10261482.76224.457D200228301026 1482.76224.457D20021950 10451484.34827.58D2002200 1117 1486.63634.592D2002 173 0 11281479.25935.042D2002 234010211479.24423.778D2002298010211479.244 23.778D1.45921.4722.9296.83.3 1.2840.160.0140.00100.00112002299010211479.24423.778D1.43621.47 22.9066693.31.2810.140.0130 0 0.001 12002 2750 10261482.76224.457D1.27 21.47 22.745.923.3 1.202 0.058 0.009 0 00.00112002 263010451484.348 27.58D1.23722.123.3375.64 1.223 0.0080.005000.00112002 252010261482.762 24.457D1.18922.123.289 53841.1660.0130.0090 00.00112002 285010211479.24423.778D2.Checkr.rlrulatodvaluesbelow5.(Optlonnl)agarnstCALPOST'~'RankedDallyEnter241%~VlrlbllityChange"(du)tableNOxConc.NOx(prib)3.Entervslucofrtte-specificRaylelphscatteringcoctticleot,tram"Rayletgh&SenSalt'6.tntrrdestredM02lNOxratloworkslwxt(defaultIs0)4.(Opttonal)Insertannualaveragere*saltroncmlratton,from"RaytelghPSeaSaW'worksheet.Leaveblank$fnotused,1.edefaultIsO..................................OUTPUT(bamdonnewIMPROVEalgorithm).................................. . . . . ... ...m,"YEARDAYHRRECEPTORCOORDINATES(km)TYPEBEXT(Source)BEXT(BKG)BEXT(Tota1)%CHANGE~~~(%)~jbrS04b-03bsOCbS?CbsPHCbaPHFban02Rankdv(t0tsl)dv(bkg)ddv2002175010271479 06924683D49362204270162256864363003900330.0020.0010004049519.947.90 2.032002 172 0 1021147924423778D41122204261871880863.604034900290.001000100040I242 9637.901.722002284010451484 348 2758D25632178 24 36311868420760357002600010.001000300993890711220023530 1026148276224 457D217421572376010158215280+550014 0.00100002017358657690.972002 2830 10261482.76224457D2293217824 09010618417530.167 0022 0.0010 001 0 0030.34748.79 7.781.012002 19501045 14843482758D1708222123936 7758i156900270012 0 001 0 0001009968.737980.?52002 2001117 1486 63634592D1625214823114762811160260 007 0 0000101987 8387640732002 1730112814/925935042D16132204 236677318012970010 008 0 0 000102978 8.611.90071200223401021147924423778D154622642419368789121300260 00900 0001029798.838.170662002 298010211479.24423778131209217822.998559840.9880133 0.0110.001 0 00010074138.337.78 0542002299 0 1021147924423/78D1237217823 027572840 986 01170010 00001012412 8347.780562002275010261482.76224457D11542178 22943 5.34840.925 0 0480.0070 0 0.001 0173148.307780.522002263 01045 1484348 27.580113722 642318350684102600070 004 0 0 00010099168.668.10.4920022520 1026148276224457D1369226424015608890 978 00120 007 0 0 00010371108.768.170.592002 2850 10211479244 23.778D1245211823031514840625 0149BE-040 0 0 0 47118.347.780.5620021610 1026148276224457D111622 04 23165509860670017000700 00010 421158.40 7.90 0.502002 150 0 10261482 762 24457D0997216722668463830.6230.021000500 00010347188.18 7.730.452002340011401481017 37 258D10712157 2264649982050125BE-040 00044617817 7.690.49200215101117 1486 63634592D09132167225844248305330 027 00050 0 00010347208151730.4220021600 1021147924423778D0932220422980425860565001200080 0 00010347198327900.422002 3460 1021147924423778D06332157 22208295820467006500020 0 0 009921798769029200224701021147924423778D0553226423 1952468905480004000200 0 0228 418.17 0.24Figure3.ExampleofAppearanceofFinished Input&OutputWorksheet.

## Appendix Details of Calculation Approach

As an example of the calculation steps, assume that the sulfate concentration resulting from emissions from a source is [SE] and the sulfate in the undisturbed natural background is [SN], for a total ambient sulfate concentration of [ST]. According to Equations 1 and 2 in the main body of this document, the total extinction due to sulfate for this combination is



### b,I(sulfate) = 

### 2.2fs(RH)*[small sulfate]+ 4.8.fL(RH)*[large sulfate], (Eq. A-1)

where



### [large sulfateT] = 

### {[Srj/20} *[ST] f[Sr] < 

### 20 ,ug3

[large sulfateT] = 

### [ST] $[ST] 

### 1 20 ,ug/m3 (Eqs. A-2)



### [small sulfate^] = 

### [ST] - 

### [large sulfate^],



### and the subscript T denotes total sulfate

For the original background, where there is no source impact, the corresponding formulas for the terms in Equations A-2 are



### [large suIfateN] = 

### [SN] ~[SN] 

### L 20 ,ug/m3 (Eqs. A-3)



### [small sulfate^] = 

### [SN] - 

### [large sulfate^],



### where the subscript N denotes natural sulfate.

Similar calculations need to be carried out for nitrates. Contributions of the other particulate components are linear and can just be calculated according to Equation 1.

If the impact due to NOz is also to be considered, then the source impact due to this component is, according to Equation 

### 1,

where @Oz] is in ppb. It is reasonable to assume that the ambient NOz concentrations under natural conditions would be so small as to cause negligible light absorption, so the corresponding term is not needed in the natural conditions calculation.

The contributions due to the various components are summed together as in Equation 1 to obtain the total extinction bext,T and the natural background extinction bexLN. The

### fractional change in extinction is then calculated as the difference, normalized by the natural background extinction

a result that can also be expressed in deciviews.

These formulas are used in the CALPOST-IMPROVE Processor. Similar formulas apply for nitrates and organics. There is no nonlinearity 

### in the remaining terms in Equation 1.CALPOST-IMPROVE ProcessorfortheEastREVISEDDRAFT2August2006CALPOSTRecalculationwith NewIMPROVE Algorithm............................INPUTfromCALPOST(based on old IMPROVEalgorithm)----------1.AtcellA7,import"RankedDailyVisibilityChange"(bext)table,includingcolumnheadings,fromCALPOST(22days,max)EARDAY HRRECEPTORCOORDINATES(km)TYPEBEXT(Mo4el)BEXT(BKGBEXT(Total)%CHANGEF(RH)bxS04bxN03bxOCbxECbxPMCbxPMFRank3.Enter valueofsite-specificRayleigh scatteringcoefficient,from"RayleighIPSeaSalt"worksheet4.(Optional)Insertannualaverageseasaltconcentration,from"Rayleigh&SeaSalt"worksheet.Leaveblankif notused,i.e,defaultis0...................................OUTPUT(based onnewIMPROVE algorithm)--------------------------.5.Checkcalculated values (Optional)below againstCALPOST'sEnter24hr"RankedDailvVisibititvNOxconc.#N/A#N/A#N/A%N/A*N/A#N/A#NIA#N/A4N/A#N/A#N/A#N/ACNIA#N/A#NjA#N/AXNIA#N/AtlN/A#N/AkN/A#N/A#N/A#N/A#N/A#N/A#N/A#NjAAN/AKN/A#N/A#N/A#N/AKNIA#N/A#NIAPNIAKN/A#NIA#N/A*N/AXN/A#N/A#N/A#N/A#N/A#NiA#N/A#N/A#N/A#N/ABNIA#N/A#N/A#N/A#N/A#N/A*N/AkNIA#N/A#N/A#N/A#NiAKN/AKNIA#N/A6.Enter desiredNOZINOxratio(defaultis0)NewYEARDAYHRRECEPTORCOORDINATESIkm)TYPEBEXTISoumeBEXT(BKGBEXT(TO~~I)%CHANG~R~~SSO~bsN03bsOCbsECbsPMCbsPMFbaNO2Rankdv(tota1)dv(bkg)1#N/A#N!AAdv0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.00PONNNNNNNNNNNNNNNNNNNNNN c~0000000000000000000000 N Cl_________.._________Modified size breakdownofnaturalbackgroundnm)concentrationsinpresence of sourcecontributions(8)-----------<-Modifiednaturalbackgroundbext(!SmnmSO41[LgnmS04][SmnmN03][LgnmN03][SmnmOC]bnmS04bnmNO3bnmOCbnmlSumAdvNewRank0.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.001

### Old 

### and New F(RH) Values Old F(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.02 1.04 1.06 1.08

1.1 1.13 1.15 1.18

1.2 1.23 1.26 1.28 1.31 New Fs(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.38

1.4 1.42 1.44 1.46 1.48 1.49 1.51 1.53 1.55 1.57 1.59 1.62 New FI(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.31 1.32 1.34 1.35 1.36 1.38 1.39 1.41 1.42 1.44 1.45 1.47 1.49 New Fss(RH) 

### 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2.36 2.38 2.42