On December 1, 2014, COMARNAT, the national regulatory committee of the Secretariat of Environment and Natural Resources (SEMARNAT), approved a proposed update by
SEMARNAT to existing emissions standards regulating particulate matter (PM), nitrogen oxides (NOX), hydrocarbons (HC) and carbon monoxide (CO) from heavy-duty diesel
engines and vehicles, including trucks, buses and large pickups and vans. The proposed modification of NOM-044-SEMARNAT-2006, PROY-NOM-044-SEMARNAT-2014 which
establishes maximum permissible emissions limits of total hydrocarbons, non-methane hydrocarbons, carbon monoxide, nitrogen oxides, and particles from the tailpipe of new
motors that use diesel fuel and that are used in new vehicles with a gross vehicle weight greater than 3,857 kilograms, as well as new complete vehicles with gross vehicle weight
greater than 3,857 kilograms that are equipped with these motors, was published in the official federal diary of Mexico, on 17 December 2014. Publication opens a 60-day
public comment period, after which another vote will be required in COMARNAT to finalize the standard. The new standards would require new heavy-duty diesel vehicles sold after January 1, 2018, to meet emissions standards equivalent to those in the United States and European Union—EPA 2010 or Euro VI standards, respectively. The proposal to fully align with the prevailing US and European standards in 2018 will require new vehicles to be equipped with diesel particulate filters (DPFs), advanced NOX aftertreatment, full on-board diagnostic (OBD) systems, and failsafes which ensure correct operation of emissions control systems.