An emissions inventory is a culmination of the yearly results gathered by each state’s Department of Transportation (DOT) within the United States. The DOT is a government agency within the United States. It measures the emissions generated by each individual vehicle over the course of a designated time frame.
Each car that has been manufactured after a designated year is required to pass an emissions allowance test to receive a required registration sticker. As such, the amount of emissions generated by the vehicle is measured and calculated to determine how much the vehicle will emit over the coarse of the inventory study. Typically, the study ranges over a long enough period to ensure that every car on the highway registered in that state has undergone an emissions test before it was able to become legally registered.
This inventory records the amount of each different kind of gas considered to be a greenhouse gas, or one that is damaging to the Earth’s atmosphere. As such, the emissions inventory is also a form of unofficial report for the federal government. The emissions inventory is used to permit the federal government to monitor the amount of hazardous gases emitted from the vehicles that travel every day within each state. These inventories are also viewable by the public, although they typically come at a pretty hefty price depending on the area the emissions inventory itself encompasses.
One of the main reasons for the emissions inventory is to have a more clear picture of the production of dangerous emissions. The amount of emissions from each area of the country can be determined using this method. Another purpose is to track the levels of emissions to ensure that they continue to decrease with the introduction of federally mandated emissions limits.
Another way that emissions are studied and that information is gathered for the inventory system is through the air quality testing equipment of the Department of Natural Resources. This equipment is used in every state to produce an accurate reading of all of the different greenhouse gases and healthy oxygen levels. It is used to ensure a proper calculation is being made by the Department of Transportation.
The information tallied and calculated by both the DOT and the Department of Natural Resources can be compared. This data is then analyzed. When the inventories show that a steady increase of different greenhouse gases is occurring, the federal government may use the information to enforce different mandates. Such mandates can govern the amount of emissions a vehicle can produce, or the types of waste materials that are allowed to be burned.