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Displaying 1 - 13 of 13 results

  • Redoing calculations if RMP*Comp is updated

    Will RMP*Comp be updated? If so, would I have to redo calculations I might already have made with an earlier version? No, you do not have to redo your work if you have already completed your consequence analyses. RMP*Comp is based on the EPA's Offsite Consequence Analysis Guidance (OCA Guidance)…

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  • Different distances to toxic endpoints with different versions of RMP*Comp

    I've noticed that for certain chemicals, RMP*Comp gives substantially different distances to the toxic endpoint than previous versions. Why? In the current version of RMP*Comp, we have incorporated new chemical-specific distance tables for ammonia, chlorine, and sulfur dioxide. The generic tables are still used for other chemicals (you can see…

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  • Distance to endpoint calculations used by RMP*Comp

    Does RMP*Comp perform some math or modelling in order to arrive at an endpoint distance, or is it simply interpolating from the tables in the EPA's Offsite Consequence Analysis Guidance (OCA Guidance)? RMP*Comp follows the procedures set out in the OCA Guidance . This means that for some scenarios, the…

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  • Why Doesn't my Output Vehicle Miles Traveled (VMT) Match my Input VMT?

    See More Frequent Questions about MOVES and Related Models . This problem usually occurs when the run specification does not include all possible vehicle and fuel types. MOVES internally allocates the input VMT to each of the source types and fuel types and only reports the VMT for the fuel…

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  • What does MOVES Assume for Future Year Fleet Fuel Efficiency and Emissions?

    See More Frequent Questions about MOVES and Related Models . MOVES reflects all fuel economy and emissions standards that were final as of the model release date. For a list of recent regulations accounted for in the most recent MOVES version, see the see the Overview of EPA’s Motor Vehicle…

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  • How does MOVES Calculate CO2 and CO2 Equivalent Emissions?

    See More Frequent Questions about MOVES and Related Models . MOVES calculates the energy it takes to operate an onroad vehicle based on energy consumption rates as explained in the technical reports Greenhouse Gas and Energy Consumption Rates for Onroad Vehicles MOVES3 (pdf) (November 2020, EPA-420-R-20-015) and Exhaust Emission Rates…

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  • Why Are There No Emissions for the Early and Late Hours of the Day for Certain Source Types?

    See More Frequent Questions about MOVES and Related Models . MOVES has no start emissions for the certain source types in certain hours of the day. While we know that a non-zero number of these source types do start late at night, our activity data on these trucks and buses…

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  • RMP*Comp and emergency response

    Can I use RMP*Comp for emergency response? No. It's a planning tool. Many other tools are available for response, including ALOHA . You can learn more by reading CAMEO tools for RMP .

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  • Minimum and Maximum Distance to Endpoint

    The Chemical Accident Prevention Provisions require the completion of a worst-case release scenario analysis (40 CFR §68.25). This analysis includes estimating the greatest distance to endpoint as defined by the parameters in §68.22. Is there a required minimum or maximum distance for the distance to endpoint in the worst case…

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  • Local meteorological data for alternative release scenarios

    For alternate release scenarios, RMP*Comp uses set values for meteorological conditions like humidity, wind speed, temperature, stability class, and so on. Is there a way to change those values? I want to use meteorology data from my own location. RMP*Comp indeed uses fixed values for certain atmospheric parameters, and does…

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  • Different results using ALOHA and RMP*Comp

    I tried running the same scenarios in ALOHA and in RMP*Comp. I got different answers. Why? The results you obtain using RMP*Comp may not closely match the results you obtain running the same release scenario in a more sophisticated air dispersion model such as ALOHA or DEGADIS. That's because of…

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  • What Pollutants are Included in “oxides of nitrogen” in MOVES?

    See More Frequent Questions about MOVES and Related Models . The definition of NOx in MOVES (NO + NO2 + HONO) is different than the standard NOx definition of NOx (NO + NO2). This change has been made to correct the exhaust NOx emission in MOVES for potential interference with…

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  • What Drives Seasonal CO Emission Trends?

    See More Frequent Questions about MOVES and Related Models . Once a vehicle’s engine/catalyst reaches operating temperature, the ambient temperature has little effect on the emissions performance of the vehicle. These “running” emission rates in MOVES have no temperature adjustment. However, during summer months at warm temperatures, MOVES assumes extensive…

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