Diesel Emissions Quantifier (DEQ)
              Frequently Asked Questions (FAQs)
              Revised April 4, 2013
United States
Environmental Protection
Office of Transportation and Air Quality
                 April 2013

Table of Contents
Administrative	3
  Logging In	3
  Saving Results	3
  Changing Your Password	3
  Activating Your Account	4
Uses and Limitations	4
  Light-duty Vehicles	4
  Congestion Mitigation and Air Quality Improvement Program (CMAQ)	4
  State Implementation Plans (SIPs)	4
  Fuel Savings/Fuel Economy Benefits	4
  CO2	4
  C3 Marine	4
  Black Carbon	5
Defaults and Emission Rates	5
  Defaults	5
  Emission Rates	5
Calculations and Units	6
  Calculations	6
  Units	6
Use in the Grant Process	6
  Choosing a  Calculator	6
  Cost-Effectiveness	7
Health Benefits	9
  Pollutants and Health Effects	9
  Counties	10
  Calculations and Accuracy	11
  Outputs and Uses	11
  Cost Benefits (Explanation and Troubleshooting)	12
  Other	13

                                             Page 1 of 21

Data Entry	13

  Multiple Technologies	13

  Fuel Types	13

  Replacement	14

  Truck Stop Electrification	14

  Trailer Refrigeration Unit	14

  Uncertainty, Missing Information, Averaging, and Diverse Fleets	15

  Fleets	15

  Baseline Emissions	15

  Idle Reduction	16

  Maintenance and Operating Costs	16

  Vehicle Definitions and Classes	16

  Verification Information	17

Input Errors	17

  Vehicle Groups	17

  Model Year	17

  Horsepower	17

  Replacement (Engine and Vehicle)	17

  Technologies	18

  Fuels	18

Currently Documented Errors	18

Appendix: Grouping Vehicles for Calculations in the DEQ	20
                                             Page 2 of 21

Logging In
    Question: I'm having trouble logging in.
    Answer: Close the DEQ and try again. If this doesn't work, delete your internet browser's history and cookies
       (usually found under "tools") and try logging in. If you still can't log in, please send an email to
       cleandiesel@epa.gov with "DEQ User Account Problem" in the Subject Line, and include your DEQ user
       account email. Meanwhile, you can create a new username and password or use the DEQ without
       logging in.

    Question: When I try to access the DEQ, I receive an error message.
    Answer: The server that hosts the DEQ can get overloaded when too many users are trying to log on at the
       same time. DEQ traffic will be high around the close of any National Clean Diesel grant competition.

       Try using the DEQ during off-peak hours (early morning, late evening or weekends).  Or you can try
       closing your browser and re-accessing the DEQ using a different browser or without  logging in.

       If you still can't access the DEQ or cannot get through a calculation without the DEQ sending an error
       message, send an email to cleandiesel@epa.gov with "Cannot Access or Complete DEQ run" in the
       Subject Line. Please include a screenshot of the error message and your user account email (if you
       logged in).

       If you can replicate the error message,  it's helpful to include all of the inputs entered before the DEQ
       sent the error message. If you can't replicate the error, please provide a description of the calculation
       you were trying to make.

Saving Results
    Question: Is there a way to save more than three "fleets" in the DEQ under a single login account?
    Answer: No. However, each "fleet" (with the exception of marine vessels) can accommodate up to 30
       "vehicle groups". Currently, each marine vessel must be a separate "fleet" (each vessel can have up to
       five marine engines). You may open multiple user accounts, but each account must have a unique email

    Question: Sometimes when trying to save DEQ results in an Excel  format, the data is saved as a text (txt) file.
       How can I get the results into Excel format?
    Answer: The DEQ allows users to save both the Summary Results  and Detailed Results in Excel or CSV
       formats. Sometimes files won't save properly because of the download settings of your browser and/or

       If your results are being saved as a text file, re-save or rename the file with an "xls" extension and Excel
       should be able to open it. If you  need the results in CSV format, save in the CSV format directly from the
       DEQ, instead of saving to Excel and then converting to CSV.

Changing Your Password
    Question: How do I change my DEQ password?
    Answer: To change your password, go to www.epa.gov/cleandiesel/quantifier. select the "Use the
       Quantifier" tab, log in, and click  on "Edit Profile".
                                            Page 3 of 21

Activating Your Account
    Question: I've submitted my account registration information, but I am unable to log in. How does my
       account get activated?
    Answer: You should have received an activation email with a validation link. You must click on this
       validation link to activate your account.

       The activation email may have been caught in your SPAM filter or your email address may have been
       mistyped on the registration form. If you can't find the activation email in your SPAM filter, try
       registering the account again.

       Occasionally the DEQ server doesn't recognize an email address ending in ".net". We are working to
       resolve this and suggest that you register with an email address that ends with ".gov, .edu, or .com" if

Uses and Limitations
Light-duty Vehicles
    Question: Can the DEQ be used for light-duty projects (i.e. diesel pickups)?
    Answer: No. The DEQ calculates emission reductions for medium-heavy and heavy- heavy-duty vehicles
       only. The Motor Vehicle Emissions Simulator (MOVES) model at www.epa.gov/otaq/models/moves can
       be used to calculate emission  reductions for light-duty or heavy-duty vehicles.

Congestion Mitigation and Air Quality Improvement Program (CMAQ)
    Question: Can the DEQ be used to estimate benefits for the Congestion Mitigation and Air Quality
       Improvement Program (CMAQ)?
    Answer: Yes, the DEQ is an estimation tool that may be used for CMAQ planning purposes.

State Implementation Plans (SIPs)
    Question: Can the DEQ be used for State Implementation Plan (SIP) calculations?
    Answer: No. When the DEQ estimates emission reductions, some default values are used. SIP and
       conformity calculations require more sophisticated modeling tools that use specific inputs. Please refer
       to your SIP and conformity guidance documents or contact your regional EPA office at
       www.epa.gov/cleandiesel/ncdc-cmt.htm for more information.

Fuel Savings/Fuel Economy Benefits
    Question: Does the DEQ provide information on fuel savings?
    Answer: No. However, when the quantity of saved diesel fuel is input to the DEQ, it can calculate the CO2
       emission reductions.

    Question: Would replacing an engine reduce CO2 (carbon dioxide) emissions?
    Answer: Maybe. In addition to reductions from burning less fuel, there is a potential for CO2 reduction from
       the new engine. Because engines  are not currently certified for CO2,the DEQ relies only the amount of
       fuel reduced to estimate CO2 reductions.

C3 Marine
    Question: How can I calculate emission reductions for C3 marine engines in ocean-going vessels?

                                            Page 4 of 21

   Answer: C3 marine engines are currently beyond the scope of the DEQ. Please see "Current Methodologies
       in Preparing Mobile Source Port-Related Emission Inventories" at
       www.epa.gov/cleandiesel/publications.htm for help in calculating these emission reductions or contact
       EPA's Helpline at 1-877-NCDC-FACTS or cleandiesel@epa.gov.

Black Carbon
   Question: Black carbon, also known as elemental carbon,  is a potent climate change agent found in
       diesel particulate matter. Does EPA have plans to include black carbon in the DEQ so its climate
       change impacts can be estimated?
   Answer: The agency is still working on guidance regarding black carbon. At this time, there are no definite
       plans to include black carbon in the DEQ.

Defaults and Emission Rates
   Question: Can you  provide more information about the DEQ default values?
   Answer: The DEQ default values were compiled using various reports and models. For more information, see
       the DEQ Default Values document at www.epa.gov/cleandiesel/documents/420bl0035.pdf.

   Question: How does the DEQ calculate the life of a vehicle? Can that value be overridden?
   Answer: For on-highway vehicles, the lifetime is set at 30 years based on our modeling. For nonroad
       applications, the lifetime is usually shorter but will vary depending on equipment type and horsepower.
       The default values for the life of a vehicle cannot be overridden in the DEQ.

Emission Rates
   In November 2010, EPA updated DEQ emission rates for highway/on-road vehicles using data from the
   Mobile Vehicle Emissions Simulator (MOVES2010) at www.epa.gov/otaq/models/moves. MOVES2010
   incorporates a number of significant improvements over the old MOBILES.2 rates, particularly in baseline
   emissions, activity data, and calculations used to estimate emissions in real-world driving conditions.
   For current and future highway/on-road projects,  it is highly recommended that you use the MOVES2010
   emission rates by selecting retrofit  year of 2011 or later.

   Question: Which "Year of Retrofit Action" should I use if my project spans several years, for instance 2008 to
   Answer: We recommend that you  use MOVES2010 emissions rates by selecting 2011 or later as the "Year of
       Retrofit Action" for the entire project, even if the retrofit activity took place before  2011.

   Question: What should I do if my project spans 2008 -2011 and my initial calculations used the old MOBILE
       6.2 emission rates  in the DEQ?
   Answer: We recommend that you  perform your final calculations using the new MOVES2010 emission rates
       by choosing 2011 as your "Year of Retrofit Action".

   Question: My project  has been completed and I've already done my calculations using  the old DEQ
       numbers.  Do I  need to re-run the DEQ using 2011 as the "Year of Retrofit Action"?
   Answer: No. If your project is closed  and you have already turned in your final report, there is no need to
       re-run the DEQ to  update the emissions savings.
                                            Page 5 of 21

    Question: What happens if I continue to use the old DEQ MOBILE 6.2 emission rates by selecting a "year of
       Retrofit Action" prior to 2011?
    Answer: You will not run into any problems using the DEQ. However, using the old MOBILE 6.2 numbers for
       your calculations will severely underestimate your emission reductions.

    Question: Why do DEQ emission factors vary from state to state for the same vehicle(s)?
    Answer: The modeling tools used to generate emission factors for the DEQ take into account a variety of
       state- and county-specific characteristics such as climate, geography, roads, and population. These
       characteristics affect emission levels, causing them to differ by state and/or county. Neighboring states
       and counties may see smaller differences than those that are farther apart.
    For projects extending beyond a single state, select the state in which the majority of activity will take place.

    Question: Can EPA provide the emission factors and methodology used by the DEQ in a spreadsheet format
       so we can do the calculations ourselves?
    Answer: The DEQ derives its emission factors from EPA's standard modeling tools - MOVES2010 for on-
       highway calculations and NONROAD2008 for non-road calculations. For more information about these
       factors and models, please visit the MOVES www.epa.gov/otaq/models/moves or the NONROAD
       www.epa.gov/otaq/nonrdmdl website.

Calculations and Units
    Question: In calculating lifetime benefits, does the DEQ consider the remaining life of the vehicle or of the
       emission control device?
    Answer: Lifetime calculations are based on the remaining life of the vehicle, not the emission control device.
       EPA assumes that once a vehicle is retrofitted, it will  remain retrofitted until the vehicle is retired.

    Question: Why do lifetime emission reductions use a vehicle's remaining life instead of the full life of the
       vehicle? For instance, I am replacing a 20 year old school bus with a brand new one. The old bus has 10
       years left while the new one has 30. The DEQ shows  lifetime emission benefits for only the 10 remaining
       years of the old bus.  Doesn't this underestimate the emissions benefit of my new bus?
    Answer: The most the old bus will emit pollutants is its remaining  life (10 years) - it will be replaced in 10
       years (when its remaining life is over) or some time before then. If it is replaced now (early
       replacement), the full 10 years of emissions will be reduced. That is the maximum that can be claimed.

    Question: Does the DEQ give results in US short tons (2000 pounds), British long tons (2240 pounds) or
       metric tons (2204 pounds)?
    Answer: Short tons.

    Question: Can the DEQ separate particulate matter (PM) by PM25 and PM10?
    Answer: No. The DEQ only calculates PM2.5.

Use in the Grant Process
Choosing a Calculator
    Question: If the DEQ is not a good match for my project,  are there other calculation tools I can use?
    Answer: You can use any model you wish as long as you explain and document your calculations.
       Here are some other models for your consideration:

                                            Page 6 of 21

       1.  Motor Vehicle Emission Simulator (MOVES) for on-road vehicles

       2.  NONROAD Model for nonroad engines, equipment, and vehicles

       3.  SmartWay FLEET Tools for freight shippers, logistics companies, and rail, trucks, drayage and
           multi-modal carriers

       4.  Argonne National Laboratory GREET Model, for estimating vehicle lifecycles and carbon
           footprints, greet.es.anl.gov

    Question: How does the DEQ calculate cost-effectiveness?
    Answer: Cost-effectiveness can be calculated by the DEQ in two ways. Both calculations are simple and can
       also be done by hand.

       First, the DEQ can provide the dollar per ton of pollutant reduced for the entire project (Total Fleet Cost
       Effectiveness). For this calculation, input the cost of the whole project before you add a "Vehicle

       Second, the DEQ can provide the dollar per ton of pollutant reduced for each unit (Capital Cost
       Effectiveness). For this calculation, enter the installation and unit costs per vehicle when you add a
       technology to your vehicle group.

       The Total Fleet Cost Effectiveness for the entire project appears only on the "Results" screen, while the
       Capital Cost Effectiveness per unit appears both on the "Results" screen and the Summary and Detailed
       results spreadsheets.

       1)  Total Fleet Cost-Effectiveness
           a)  The DEQ totals the entire project funding amounts entered on the first DEQ screen (shown
              below). This is the Total Project Cost.
                                             Page 7 of 21

    Enter Fleet Information
       Fleet Name   School Bu
       Fleet Type
                 On Highway NonRoad  v
     Do you want to estimate the total cost effectiveness of the project?Yes No

     Total cost effectiveness numbers are based solely on the user inputs below

Other Federal S


Local 5



Privates ^300

Match Lev. S 2EOOO


Other S

Unknown S

State S

3333 |

1000 |

o H

    b)  After the Vehicle Groups have been entered, the DEQ calculates the total lifetime emission
       reductions by pollutant (NOx, PM, HC, CO, and CO2) for the entire fleet. This is the Total Lifetime
       Tons Reduced.

    c)  The DEQ then divides the Total Project Cost by the Total Lifetime Tons Reduced for each of the
       five pollutants. The results are shown in dollars/ton on the bottom of the Emission Results
       Page. The results are currently not shown in outputs that are downloadable in Excel and CSV
       formats. However, it is a relatively simple calculation that can be done by hand using DEQ

2)  Capital Cost-Effectiveness  is calculated using the installation and unit costs entered in the DEQ
    screen  shown below. It does not include things like project administration costs and overhead.

    Capital  Cost-Effectiveness is calculated by adding the Unit Cost and Installation Cost for each
    technology and dividing the sum by the Total Lifetime Tons Reduced for each  of the five pollutants.
    This value is displayed both on the Emissions Results page and the outputs that are downloadable
    in Excel and CSV formats.
                                       Page 8 of 21

   Enter Fleet  Information
                                                                                        Start Over
    Idle Reduction
                    Fleet Type On Highway  Non-road
                         State Kentucky
                                                         Start Over
    Long Haul Idle
                      Quantity 2

                         Type On Highway

                   Target Fleet Long Haul

              Class Equipment Class 8a

                    Model Year 1996

                 Retrofit Year of 2012
                      Fuel Type Regular Diesel
                               (ULSD), 1 5 ppm

                    Fuel Volume 33334

             Veh. Miles Traveled 1 00000

                    Idling Hours 2400
                                           New Technology
                                           Vehicle Grot
Technology Type
 Emissions Control Devices
 Diesel Oxidation Catalyst
         Apply To \2
(out of 2} with no technology
     Reduction by Pollutant
              NOX % [iT
              C02 % E"
                                                   Install Cost |1000

                                                     Unit Cost 6000
                         S per vehicle

                         S per vehicle
                                               Edit Group
                                                               Save Technology
Health Benefits
Pollutants and Health Effects
    Question: Which health effects of diesel PM2.5 are included in the cost/benefit calculation in the Health
        Benefits Module?
    Answer: The benefits of reduced diesel emissions are based on avoided incidences of the following:
            Premature mortality
            Chronic bronchitis
            Acute bronchitis
            Upper and lower respiratory symptoms
            Asthma exacerbation
            Nonfatal  heart attacks
            Hospital admissions
                                                Page 9 of 21

          Emergency room visits
          Lost work days
          Restricted-activity days

    Question: Does the DEQ estimate reductions in total particulate matter or fine particulate matter (PM2.5)?
    Answer: The DEQ estimates reductions in PM2.5 and that is what is used for determining health benefits.  For
       additional information, please refer to the Health Benefits Methodology at

    Question: Is diesel particulate matter the only pollutant considered in the Health Benefits Module?
    Answer: Yes. There are likely benefits from reducing other pollutants, such as ozone and air toxics, but the
       DEQ cannot quantify these benefits at this time.

    Question: How do I determine in which counties the emission reductions take place?
    Answer: The DEQ requires you to choose one state where the retrofits take place.  For projects that span
       multiple states, such as long-haul trucks and locomotives, select the state where the majority of
       emissions are generated.

       Once the DEQ calculations are completed and you go to the Health  Benefits tab, you can allocate the
       emission reductions among up to five counties (in multiple states). Note that the Health Benefits
       Module is not asking whether pollution from one county is drifting into another; it's asking where the
       vehicles that are reducing their emissions are operating.

    Question: My county is "flagged." What does that mean?
    Answer: The Health Benefits Module will flag results for counties where there may be an  under or over
       estimate of health benefits due to the migration of emissions into or out of the county.

       For counties with a large quantity of emissions flowing into the county, the results are flagged with the
       following message: Benefits estimates are "flagged" for this county, indicating that we have less
       confidence in these results due to a large amount of inter-county transport of emissions. The impacts
       estimation tool may be overestimating the benefits for emission reduction projects in this county,
       because it has relatively few emissions compared to surrounding areas. As a result, this county is likely to
       be a net importer of diesel emissions, and air quality is significantly affected by emissions in upwind
       counties. Please take this increased uncertainty into account when interpreting your results.

       For counties with a large quantity of emissions flowing out of the county, the results are flagged with
       the following message: Benefits estimates are "flagged" for this county, indicating that we have less
       confidence in these results due to a large amount of inter-county transport of emissions. The impacts
       estimation tool may be un derestim a tin a benefits for emissions reduction projects in this county, because
       it has a relatively high density of emissions compared to surrounding areas. As a result, this county is
       likely to be a net exporter of diesel emissions, and many of the benefits of reducing these emissions are
       likely to take place in downwind counties. Please take this increased uncertainty into account when
       interpreting your results.

    Question: When I enter the same data for retrofit projects in different counties, why do I  get different
       health  benefits?
                                             Page 10 of 21

    Answer: One of the main factors in determining the health benefits from reduced emissions is the
       proximity of people to where those emissions would have been generated. If a certain level of
       emission reduction is assigned to a census tract with a larger area, it will result in a lower
       concentration as the  pollution is being spread over a greater area. The opposite  is true as well.
       Assigning emission reductions to a smaller area census tract will result in higher  concentrations.

       In addition, if a certain level of emission reductions is assigned to a less populated census tract, fewer
       people will be exposed resulting in a lower concentration ratio. Again, the opposite is true: emissions
       assigned to higher-populated tracts leads to a higher concentration ratio.

Calculations and Accuracy
    Question: How are benefits of reducing diesel particulate matter calculated?
    Answer: The Health Benefits Module uses a county "look-up table", which includes estimated benefits per
       ton of PM2.5 reduced for each county in the  United States.

       The user answers a set of questions about their project. Once the DEQ estimates the emission changes,
       the Health Benefits Module uses the "look-up table" to estimate the health benefits associated with the
       PM 2.5 reductions for the specified county. The combined monetary benefits of avoided mortality and
       avoided morbidity (i.e. non-fatal illness) for the selected counties are displayed.

       As part of the Quality Assurance process, EPA has also developed a table using on-road and nonroad
       diesel PM 2.ssource tables. These tables and more are available in the Health Benefits Methodology at

    Question: How accurate are the Health Benefits Module estimates?
    Answer: The methodology used to estimate health benefits was peer-reviewed both inside and outside EPA
       and many of the suggestions were incorporated. The module includes data and modeling from several
       existing EPA tools, such as the National Emissions Inventory (NEI), the National Air Toxics Assessment
       (NATA), and  the Environmental Benefits Mapping and Analysis Program (BenMap).

       The benefits reflect reductions only in fine particulate matter. They do not include  benefits from the
       reduction of other pollutants, including air toxics.

       The estimates are based primarily on county-level data and do not capture smaller-scale variability, such
       as living very near a retrofitted diesel source or regularly riding a retrofitted school bus.

       The results also do not include the impact of emission sources from Canada or Mexico. Results for
       border states will  not reflect these potentially significant sources of transported  emissions.

       The results are best used to assess the relative benefits among different locations or retrofit projects.

       For a complete discussion of the accuracy of these estimates, please see the chapter titled
       "Uncertainties,  Limitations, and Quality Assurance" in the methodology document at

Outputs and Uses
    Question: What  information does the Health Benefits Module provide?
                                             Page 11 of 21

    Answer: This module provides information on health benefits from reduced exposure to diesel PM 2.s

       The DEQ requires users to input detailed information regarding their retrofit projects. The DEQthen
       calculates the emission reductions for particulate matter (PM), nitrogen oxides (NOx), hydrocarbons
       (HC), carbon monoxide (CO), and carbon dioxide (CO2).

       The Health Benefits Module allows users to identify the counties where the emission reductions are
       taking place and to estimate the monetary impact of the resulting health benefits. These estimates are
       based on the change in fine  particle concentrations and do not reflect changes in any other pollutants.

       Users can save and export files summarizing the emissions and health effects estimates. There is also a
       Health Benefits Methodology at www.epa.gov/cleandiesel/documents/420bl0034.pdf that explains the
       methodology used  to estimate the health benefits and the limitations of the estimates.

    Question: How can this health benefits information be used?
    Answer: The Health Benefits Module is a helpful tool for preparing estimates and understanding benefits of
       specific emission diesel reduction projects. It can help in making informed decisions by comparing the
       benefits of several  diesel retrofit options. It can also provide an estimate of benefits for EPA grant
       applications and help build public support for such projects. It should not be used in the calculation of
       emission reductions for State Implementation Plan (SIP) or conformity determination.

Cost Benefits (Explanation  and Troubleshooting)
    Question: Why does the Health  Benefits Module use annual costs and benefits?
    Answer: Diesel retrofit  projects tend to be capital-intensive in the first year due to the purchase and
       installation of new  equipment or parts. The benefits, however, are spread out over many years as
       people continue to receive health benefits from the reduced emissions.

       In order to  properly compare costs and benefits, this difference in timeframes must be addressed. We
       annualize the costs and the benefits so the user can tell at a glance if the benefits outweigh the costs on
       an annual basis. They also provide an indication of the scale and magnitude of the expected costs and
       benefits over the lifetime of the project.

       Annualized costs are not the out-of-pocket costs in the first year, but what would be paid each year if
       the out-of-pocket costs were distributed the over the life of the engine. This is similar to the way a
       mortgage distributes the purchase price of a home over 30 years. If you used a loan to purchase the
       retrofit technology, the annualized costs are roughly what the loan payments might look like.

       Lifetime costs and benefits can be estimated by multiplying the annual costs or benefits by the number
       of remaining years  in the life of the retrofitted vehicle. While the lifetime estimate does not take into
       account factors such as discount rates for benefits in future years or population growth, it does provide
       a rough estimate.

    Question: Why are there no costs in the "Results" table of the Health Benefits Module?
    Answer: The Health Benefits Module estimates the annualized costs from the "install cost"  (labor) and
       "unit cost"  (equipment) of the project, which are entered into DEQ's Fleet Information screen under
       "Add a New Technology." If  no cost information is entered, no cost information will appear in the
       benefits results table.

                                            Page 12 of 21

       Please note, funding information can also be entered on the first screen of the DEQ by answering yes to
       "Do you want to estimate the total cost effectiveness of the project?" These are assumed to be total
       project costs,  including overhead, and are not used to estimate annual costs.

    Question: I am trying to determine the health benefits for a marine engine repower project.  While there
       are significant PM reductions, why do the benefits come up as $0?
    Answer: The health benefits calculation depends on the PM reduction in tons. Sometimes, that reduction
       may be lower than you realize and the benefits may be so close to zero that they are accidentally
       truncated. Please download the Summary Results for both the DEQ calculation and the Health Benefits
       calculation in  Excel or CSV and send it to cleandiesel@epa.gov

    Question: Where  can I get more information about particulate matter in diesel exhaust?
    Answer: For information about particulate matter, visit www.epa.gov/air/particlepollution

Data Entry
Multiple Technologies
    Question: Can I select combined emission control devices like DOC+CCV (Diesel Oxidation Catalyst +
       Closed Crankcase Ventilation) or DPF+CCV (Diesel Particulate Filter + Closed Crankcase Ventilation)?
       How about CCV by itself?
    Answer: CCV is included under "Emission Control Devices" as DOC+CCV, or DPF+CCV, but it is not listed as a
       stand-alone retrofit technology. To use CCV as a stand-alone technology, select "Other Emission Control
       Devices" from the "Technology" menu and enter the reduction percentages provided by  the CCV

    Question: Can I select multiple technologies such as engine  repower with DOC or DPF?
    Answer: Some technologies cannot or should not be installed together (e.g. DPFs and Partial  Flow filters).
       However, many technologies can be used at the same time.

       To add multiple technologies to a vehicle group, select the first technology and save it to the vehicle
       group. Then select the second, saving it to the same vehicle group. The screen always returns to the
       first vehicle group after adding a technology, so  if there  is more than one vehicle group, make sure the
       technology being added to the correct group.

Fuel Types
    Question: The emission factors for NOx,  PM, HC, and CO do not change when I select a different fuel
       type for my Vehicle Group. Why are these emissions not different for CNG and ULSD?
    Answer: Fuel type and volume are used to calculate only C02 emissions. This is done by converting
       non-diesel fuel amounts to diesel-equivalent gallons, and then calculating CO2 emissions  based on
       the diesel carbon content.

    Question: How does the DEQ estimate emission savings for switching from one fuel type to another?
    Answer: When you enter the vehicle information on the "New Vehicle Group" screen, select  the fuel type
       being  used before the retrofit. Then go to "Add a New Technology," select "Fuel Options" and the fuel
       type that will  be used after the retrofit. You can apply as many additional technologies as you need to.
                                            Page 13 of 21

    Question: When I select CNG as the new fuel for my old diesel vehicle, all of the reduction percentages are
       zero. Why is this?
    Answer: The DEQ is primarily designed to calculate emission reductions for vehicles that use diesel fuel
       (ULSD, LSD, etc). All other fuels (biodiesel, CNG, LNG, etc) are converted by the DEQ to a diesel
       equivalent ("Calculated Fuel Volume") before any calculations are performed. Currently, the DEQ is not
       able to provide emission reductions for CNG and LNG fuel conversions because fuel-specific emission
       factors are not available in all cases. For more information, please visit the Alternative Fuel Conversion
       website at www.epa.gov/otaq/consumer/fuels/altfuels/altfuels.htm

       As a workaround for this, create two vehicle groups in the DEQ, one with  a baseline engine using diesel
       fuel, and one with a  baseline engine using the new fuel (you would need to know the annual amount of
       new fuel the used after the conversion, the  annual of miles the vehicle would travel, and annual hours it
       would idle). Comparing the outputs for these two vehicles provides the CO2 emission reductions from
       the fuel conversion.

    Question: Does the DEQ calculate emission reductions for engine replacements?
    Answer: Yes. Under "Technology Type," select "Engine Replacement/Repower." Then under "Technology"
       select "Engine Replacement."

    Question: Can the DEQ be used to calculate emission reductions from replacing a diesel engine with
       electric technology?
    Answer: Installing electric technology reduces diesel emissions to zero. To quantify the reductions, start by
       entering the fleet information. For "Technology Type," select "Emission Control Devices," and for
       "Technology, " select "Other Emissions Control Devices." In the "Reduction by Pollutant" box, enter
       100% for each of the pollutants. The DEQ will quantify the project's emission reductions using
       reductions of 100 percent.

    Question: For engine repower or replacement projects, should "engine replacement/repower" be selected
       as the technology or should the DEQ be run twice, first with the baseline engine and then with the new
    Answer: Please select "engine replacement/repower" as a technology.
Truck Stop Electrification
    Question: How are emission reductions determined for Truck Stop Electrification (TSE)?
    Answer: The DEQ calculates TSE emission reductions the same way it does for other idle reduction
       technologies. The best calculations will result from inputting your best estimates of the number and
       type of trucks that would use the TSE facility, as well  as the expected reduction in idle hours.

Trailer Refrigeration Unit

    Question: How can I  calculate the emissions reduced by replacing a trailer refrigeration unit (TRU) in a box
    Answer: TRUs are not currently a technology option in the DEQ. As a workaround, create a Vehicle Group
       for the TRU by selecting "Non Road", "Stationary" and "Power Generation". Then select "Engine
       Replacement" as the technology. Be sure that all Vehicle Group inputs (model year,  hp, usage rate, fuel
       usage, etc) are for the TRU and not for the tractor-trailer.

                                            Page 14 of 21

Uncertainty, Missing Information, Averaging, and Diverse Fleets
    Question: We have a project with a variety of fleet components, but we are unsure of the exact vehicles
       that will be in the program. What should we use for the DEQ calculations?
    Answer: If you are unsure of the exact fleet, you should use your best judgment and any past history you
       have with such a program to make estimates in the DEQ.

    Question: What if I don't have all of the information required to use the DEQ?
    Answer: The DEQ will self-populate some default values when you select "Get Default Values." Other
       defaults must be input manually. They can be found in the DEQ Default Values document at
       www.epa.gov/cleandiesel/documents/420bl0035.pdf.  You can also make your own estimates;
       however, using real-life data is highly recommended.

    Question: For nonroad vehicles, the DOC unit cost varies depending on engine size. Can we average the
       costs per unit or must we do a  separate run for each application?
    Answer: You can either do separate runs for each unit or average them, but the separate runs will give you
       more precise results.

    Question: How do you estimate emissions for a fleet with multiple, diverse vehicles? Must a separate
       calculation  be performed for each vehicle?
    Answer: You may generate a report for each vehicle or group of similar vehicles. Alternately, you may run a
       single report using "average" inputs to minimize the number of runs. Separate runs will give you more
       precise results. For more information on the best ways to group vehicles and still ensure accuracy, refer
       to the Appendix of this document.

    Question: How do I handle a project with both on-road and nonroad vehicles?
    Answer: The DEQ can support multiple Vehicle  Groups, including a mix of on-highway and nonroad in the
       same Fleet. Include the on-road/highway vehicles in one vehicle group and the nonroad in another.

    Question: Which inputs are for a single vehicle and which are for the entire fleet?
    Answer: All of the inputs except for Fuel Volume should be entered for per vehicle or engine. Fuel Volume
       should be entered as a total for the entire Vehicle Group.

Baseline Emissions
    Question: How can I calculate baseline emissions using the DEQ?
    Answer: To calculate baseline emissions, begin  by entering the information about your fleet. When you
       "Add a New Technology," select "Emission Control Devices" for "Technology Type" and "Other Emission
       Control Devices" for "Technology." This will default the  reduction percentages to zero and the DEQ will
       calculate only the baseline emissions. Please note, if you do not add any technology to your fleet, the
       DEQ will calculate baseline emissions and display them on the Emission Results Screen, but the results
       won't appear on the DEQ Summary Results spreadsheet.

    Question: For engines with OEM catalysts,  adding a new retrofit device sometimes requires the removal of
       the original catalyst. How does the DEQ take the removal of the catalyst into consideration when
       calculating emission reductions?
    Answer: The DEQ's baseline emission factors are always based on certified engine configurations, which
       include OEM catalysts. Whether a retrofit device is added to a vehicle with an OEM catalyst or to a

                                            Page  15 of 21

       vehicle that has had the catalyst removed to accommodate a new device, the DEQ calculates emission
       reductions from the certified OEM baseline. Please keep in mind that project can only claim emission
       reductions from a vehicle/engine's certified baseline.
Idle Reduction
   Question: Are idling hours included in the nonroad "Usage Rate"?
   Answer: Idling hours are included in the default "Usage Rate" for nonroad vehicles.  If you are entering
       actual "Usage Rate" hours, be sure to include idling hours.

   Question: The idle reduction technologies display emission reductions for NOx, PM,  and CO2 only. What
       about HC and CO?
   Answer: Although idle reduction technologies may reduce HC and CO emissions, idling emission factors are
       available only for NOx, PM, and CO2 and only for on-highway vehicles.
    Question: When calculating emission reductions for idle reduction technology, the reduction percentages
       that populate the input screen are not the same as those shown on the downloaded spreadsheet. Why?
    Answer: For on-highway vehicle calculations, the DEQ uses two sets of emission factors, idle emissions and
       running emissions. When a user applies an idle reduction technology, the reduction percentages that
       populate the input screen reflect only the idle emissions. The downloaded spreadsheet shows the
       reduction percentages for both idling and running emissions. For instance, an idle reduction technology
       may reduce a vehicle's idle emissions by 90%, but it may reduce the vehicle's overall emissions by only
       10%. This will vary based on the vehicle idling hours relative total usage hours.
Maintenance and Operating Costs
    Question: How can I include project maintenance and operating costs in the DEQ estimates?
    Answer: These  costs do not have specific input fields in the DEQ. They may be included as part of the total
       project costs. Enter them as part of the total funding on the first screen by answering "yes" to the
       question "Do you want to estimate the total cost-effectiveness of the project?".

Vehicle Definitions and Classes
    Question: How does the DEQ define a bus? Does it include hotel or airport shuttles?
    Answer: The DEQ calculates emission for only medium heavy-duty and heavy heavy-duty vehicles
       (Classes 5-8). This includes school buses and transit buses. Shuttle buses are usually Class 4 or 5, but
       please verify this is the case for your specific fleet. For a more information on vehicles and weight
       classes, please see the DEQ Default Values document at

    Question: Where can I find the definition of the different vehicle classes? Are they the same as DOT classes?
    Answer: For highway vehicles, medium heavy-duty and heavy heavy-duty vehicles are included in the DEQ.
       The classes are defined by US DOT by gross vehicle weight rating (GVWR).
          Class 5; 16,001 -19,500 Ibs GVWR
          Class 6; 19,501 - 26,000 Ibs GVWR
          Class 7; 26,001 - 33,000 Ibs GVWR
          Class 8a; 33,001 - 60,000 Ibs GVWR
          Class 8b; 60,001 Ibs GVWR and over

                                            Page 16 of 21

    For further definitions of vehicles and weight classes, please see the DEQ Default Values document at

Verification Information
    Question: Does EPA have a list of engine family names that have been approved for verified products?
    Answer: No.  Unlike CARB, EPA does not issue a list of engine family names for each technology that
       has been verified. Please refer to the Verified Technology Listing at
       www.epa.gov/cleandiesel/verification/verif-list.htmtfretrofit for specific engine model
       applicability and general operating criteria.  Engine certification data, including engine family
       names, are available at www.epa.gov/otaq/certdata.htmtflargeng

Input Errors
Vehicle Groups

    Question: I get the following error message when I try to add a vehicle group to a saved fleet: "An
       Unexpected Error has Occurred. We are sorry, the Diesel Emissions Quantifier has experienced an
       unexpected error. The details of this error have been logged and the development team has been
       notified. If you left your browser inactive for over 30 minutes, this error is due to your session timing
       out." What should I do?
    Answer: If possible, take a screenshot of the error page and send an email to cleandiesel@epa.gov. with
       "Could not Update Saved Fleet" in the subject line. Also include as much info as you can about the
       inputs you entered, info about the vehicle group, etc, as well as your DEQ user email.  Meanwhile, try
       logging out, closing the browser and then logging back in again. You can also try running the DEQ
       without signing.

    Question: Is there a limit to  how many Vehicle Groups can be included in one Fleet? I have entered 47
       Vehicle Groups and when I try to  quantify emissions, I get an error message saying the DEQ is
       experiencing an error.
    Answer: We recommend that you keep the number of Vehicle Groups under 30.

Model Year
    Question: Sometimes the DEQ does not allow me to select a specific model year for my vehicles.
    Answer: Depending on the vehicle type, the DEQ may assume that only certain model years are able to be
       retrofitted. If the model year of your vehicle is not displayed as an option, select the closest model year
       that is available.

    Question: The DEQ does not list the horsepower of my nonroad vehicle. The nearest available horsepower
       option is  either too high or too low. What should I do?
    Answer: We recommend using the closest available horsepower option. At this time, the DEQ does not have
       data for every available  horsepower, as data collection and approval of emission factors may take years.

Replacement (Engine and Vehicle)
    Question: How do I calculate emission reductions for vehicle replacement using the DEQ?
    Answer: The  DEQ does not offer an option for vehicle replacement. To calculate emission reductions for a
       vehicle replacement project, please select "Engine Replacement" for "Technology Type".

                                            Page 17 of 21

    Question: If idle reduction is not an option for nonroad equipment, how can I quantify emission reductions
       for automatic shutdown devices on nonroad vehicles?
    Answer: At this time the DEQ does not support idling strategies in nonroad engines. Please consider using
       another calculation method.

    Question: When using the DEQ, only technologies that have been verified are listed. How can I include an
       Emerging Technology in the calculations?
    Answer: Please refer to the Emerging Technology List at www.epa.gov/cleandiesel/verification/emerg-
       list.htm  and manually input the projected emission reductions for PM NOx, HC and CO.

    Question: The emission reduction results for several technologies I'm using, such as direct fired heaters, are
       0%. What might be the problem?
    Answer: If the "Idle Hours Reduced" was left blank, then you will get 0% reductions. Be sure to enter the
       number of idle hours in this field.

    Question: How do I calculate emissions reductions if the fuel blends we are using, like high blends of
       Biodiesel plus ULSD, are not listed?
    Answer: The DEQ results are estimates, so please select the option that is closest to your real-world

    Question: The DEQ has selections for B-20 and B-100 but nothing in  between. The National Clean Diesel RPF
       indicates that any blend of Biodiesel (B-5 to B100) is eligible. How do I calculations on something other
       than B20 and B100?
    Answer: The DEQ can't accommodate blends other than B20 and B100 at this time. You may select the
       option that is closest to the fuel you are using or use another calculation tool more geared to fuels.

    Question: My organization has 20 trucks and we'll be replacing the engines in 10 of them. For the "Fuel
       Volume" for the fleet, do we enter the total fuel consumed by the 20 trucks in the fleet or just the 10
       that are going to be replaced?
    Answer: Create a Vehicle Group of 20 vehicles, then select "Engine Replacement" and apply it to 10 of the
       20 vehicles. For "Fuel Volume", enter the combined fuel consumption for the entire Vehicle Group (all
       20 trucks).
Currently Documented Errors
    The DEQ is an estimation tool only and users may not be able to quantify all possible scenarios. EPA suggests
    you familiarize yourself with the options. These are outlined in
          Health Benefits Methodology  www.epa.gov/cleandiesel/documents/420bl0034.pdf
          Current Methodologies in Preparing Mobile Source Port-Related Emission Inventories

    If the DEQ is not a good fit for your project, you may want to download the emission factors from
    www.epa.gov/otaq/nmim.htm and make your own calculations. You can also use other available data

                                            Page 18 of 21

sources.  If you are using the DEQfor a DERA application, you can use any documented methodology to
calculate emission reductions as long as you cite the source in the application.

Below are some common errors and suggested work-around solutions. If the problem you are encountering
is not listed, please log out, restart the DEQ, and try again. If the error occurs again, please send your inputs
and error message (screen shot or copied and pasted) to cleandiesel@epa.gov.

Problem: I can't log in to my user account.
Solution: Send an email to cleandiesel@epa.gov with the subject line "User Account Problem" and include
    your log-in email. Meanwhile, you  can create a new user account using a different email address.

Problem: My previously saved scenarios are not working.
Solution: Due to updates to the DEQ structure, some saved scenarios may no longer work properly. If you
    encounter this, please delete the old Fleets and recreate them.  In some cases, users are able to access a
    saved Vehicle Group, but are not able to quantify it. This can be fixed by deleting the existing
    technology, re-entering it, and then clicking on "Quantify Emissions."

Problem: I can't find Total Cost-Effectiveness on the exported Results spreadsheets.
Solution: Total Cost-Effectiveness is displayed on the Summary Results screen, but it is not yet available on
    the spreadsheets. Please refer to the screen directly after clicking "Quantify Emissions," or calculate
   The DEQ calculates Total Cost-Effectiveness by taking the total project funding and dividing it by the
    total Lifetime Tons Reduced of each pollutant.
   The DEQ calculates Capital Cost-Effectiveness by taking the total Unit Cost and Installation Cost for each
    technology added and dividing that by the Lifetime Tons Reduced for each pollutant.

Problem: The Lifetime Emissions equal the Annual Emissions.
Solution: Based on our modeling, the DEQ uses standard lifetimes for vehicles and non-road equipment,
    even though they may be used longer. The DEQ assumes if a vehicle is older than its standard life, its
    remaining life is just one year, resulting in Lifetime Emissions equaling Annual Emissions. One work-
    around is to multiply the Annual Emissions by your estimate of the vehicle's remaining life.
                                         Page 19 of 21

Appendix: Grouping Vehicles for Calculations in the DEQ

    The DEQ is designed to provide emission reduction estimates for a variety of fleet and technology options. If
    your project has a mix of vehicle and engine types, you do not have to run the DEQ for each vehicle. You can
    divide the fleet into several groups and run the DEQ several times. The following guidelines are based on the
    on-road and nonroad emission standards. For more information, see
         On-Highway Heavy Duty Compression Ignition Exhaust Certification Emission Standards
         Non Road Compression Ignition Exhaust Emission Standards

1)  First, separate the DEQ Calculation Groups for multi-sector projects into Highway/On-road, Nonroad, and
    Marine.  Marine retrofits require a separate DEQ run for each vessel, so the following will apply only to
    Highway/On-road and Nonroad vehicles.

    a)  On Highway.

       i)  First, group all on-highway vehicles into their respective Target Fleets:
          (1) City/County Vehicle
          (2) Delivery Truck
          (3) School Bus
          (4) Transit Bus
          (5) Refuse Hauler
          (6) Emergency Vehicle
          (7) Long Haul
          (8) Short Haul

       ii)  Within each Target Fleet, group vehicles based on the Class/Equipment:
          (1) School Buses
          (2) Transit Busses
          (3) Class 5
          (4) Class 6
          (5) Class?
          (6) Class 8a
          (7) Class 8b

       iii) Next, divide the Class/Equipment groups by the following Model Year ranges (based on the On-
          Highway PM level emission standards ) :
          (1) Pre-1987
          (2) 1988-1990
          (3) 1991-1993
          (4) 1994-1997
          (5) 1998-2003
          (6) 2004-2006
          (7) 2007-2010
                                           Page 20 of 21

    iv)  Finally, within each Model Year group, divide your vehicles based on the type of retrofit technology
       that will be applied (i.e. Diesel Oxidation Catalyst + CCV, Engine Replacement, etc)
b)   Nonroad (non-marine vessels/engines)
    i)   First, group all nonroad vehicles into their respective Target Fleets:
       (1) Agriculture
       (2) Construction
       (3) Ports and Airports
       (4) Rail
       (5) Stationary

    ii)  Within each Target Fleet, divide the vehicles based on the Class/Equipment (too many to list here,
       and realize that some nonroad equipments can overlap so you could have fewer groups than you

    iii)  Within each Class/Equipment group, divide by the following Horsepower/Model Year combinations
       (based on nonroad emission standards for NOx, PM, NMHC+NOx and CO):
          (a) <11 hp and pre-2000 (Tier 0)
          (b) <11 hp and 2000-2004 (Tier 1)
          (c)  750 hp and pre-2000
          (w)  > 750 hp and 2001-2010

    iv)  Finally, within each Horsepower/Model Year group, divide your vehicles based on the type of
       retrofit technology that will be applied (i.e. Engine Replacement, Engine repower, Hybrid
       Replacement, etc.)
                                        Page 21 of 21