20251215 13172100 1.0 TRUE 150000000 5000 FGDC HDV annual start count at census tract level The dataset integrated big data and CARB's on-road emission inventory EMission FACtor (EMFAC), focusing on heavy duty vehicles for year 2022. <DIV STYLE="text-align:Left;"><DIV><DIV><DIV STYLE="font-size:12pt"><P><SPAN>The purpose of this start count map is to quantify and map vehicle start count at a community scale at census tract level. This can help us develop effective strategies to reduce exposure, especially in communities that experience disproportionate air-quality burdens.</SPAN></P></DIV></DIV></DIV></DIV> 20251215 Yucheng He California Air Resources Board 4001 Iowa Ave. Riverside CA 92507 US 9512367817