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Lesson 15 - Non-Road Mobile Sources

15.4 - Using the TEISS User Defined Calculators to Estimate Non-Road Emissions

TEISS provides a way for users to create calculators for any kind of source that is not included in TEISS. You will need to have emission factors and know the equation that you want to base the calculator on. The example below demonstrates how to create User-Defined Calculators for Non-Road sources. You can use this same method to create calculators for any kind of source.

First, click on the calculator button on the main toolbar.


At the bottom of the calculators list, you will see a folder called User Specified Calculators:

Right click on the folder and select Add Folder to create a folder to put your Non-Road Calculators in. Name it "Non-Road Calculators":

Now right click on your new Non-Road Calculators folder and select Add Calculator:

The Add a New User-Specified Calculator wizard will open. The first tab prompts you to create a name for the calculator. For this example, let's use 4-stroke Rubber Tire Loaders, a fairly common kind of construction equipment. You can add extra descriptive information in the field provided. For this example, we'll include information on where this emission factor came from.


In this tab, you also specify the input. For this example, we'll use "Vehicle" because we will use the per vehicle emission factor to calculate the emissions. If you were using the hours of activity emission factor, you would select Unit as the input material and in the Description box above, you would add a sentence saying "The input units are in hours of vehicle activity."


Click on the SCC & Pollutants tab to continue building the calculator. At this point, you will need to open the Non-Road emission factor spreadsheet and find "4-stroke Rubber Tire Loaders" in it. For many equipment types, there will be several rows of emission factors, corresponding to the possible horse-power ranges for that type of vehicle. You must either gather information to find out what horsepower is most appropriate to use or make your best guess and use the emission factors in that row to build your calculator.

Notice that the SCC code for that equipment type is listed in the spreadsheet. Copy the SCC from the spreadsheet. Go back to the User Defined Calculator wizard in TEISS and click on Add in the "Specify SCCs Applicable to the Calculator" part of the window. That will open the SCC search function, where you can search for that specific SCC and select it to add to this calculator.

After you have selected your SCC, click on the Add button in the "Specify Pollutants and Emission Factors" part of the window. You will be prompted to search for pollutants. Once you select a pollutant, you must enter the "tons/year/vehicle" emission factor for that pollutant from the spreadsheet. Unfortunately, you can not paste them into the calculator, you'll have to write them down, and then enter them in. Repeat this operation for each pollutant you want to calculate emissions for.

If you want to use the hours of activity emission factor, you would create the calculator in the same way, except you would use the "tons/year/hours of use" emission factors from the spreadsheet.

Click on the Inputs & Equation tab to continue. In the Input Name field, type out what will need to be entered into the calculator. For this example it is "Number of Rubber Tired Loaders." Then you need to type in the word "Vehicle" in the Units field.


Next, you will build the equation. First click on the input variable you just entered, so the entire row is highlighted in blue. Then click on the button to insert the input variable into the equation. You will see the name of the variable appear in the Equation field after you do this. Then click on the multiplication symbol button to add it to the equation. Then click on the button that says Factor. The factor button tells the calculator that you want it to multiply the input by all of the emission factors you entered in the previous tab.

Finally, you need to tell the calculator what the input units are. Since the emission factors are in tons/vehicle, and you are multiplying them by number of vehicles, the output will be in tons. Use the search button next to the Output Unit field to find Tons and select it.

You are now ready to test your calculator. Click on the Test button at the bottom of the window. The calculator will appear as it will look when you use it in the outline. For this example, it will look like this:

To test the calculator, enter a number of Rubber Tire Loaders into the Value field, then click Calculate. You will then seen the result in the Resut field under pollutants.

This calculator is now ready for you to use in your project. You will be able to use it through the Outline view of TEISS. The results calculated can be imported into your outline in the same manner as the calculators included in TEISS. You will add the area process in the Non-Road Mobile Sources, Area Location folder for your tribe. You'll use the same SCC that you found in the spreadsheet to identify the process. When you add the emission period, go to the Estimate tab, then click the Add & Execute button. When the Calculator Executor window appears, you will see a User Specified tab. Clicking on that tab will display all of the user specified calculators that you have built. Select the calculator you want to calculate emissions and import the results into your outline.

End of Lesson 15.4

Lesson 15.3

Lesson 16