On December 1, 2014, COMARNAT, the national regulatory committee of Mexico's 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 on-highway heavy-duty diesel engines and vehicles, including trucks, buses and large pickups and vans. Following a 60-day public comment period that ends in mid-February, another vote will be required in COMARNAT to finalize the standard.

The new heavy-duty vehicle emissions standards, aligned with standards in place in the rest of North America and in the European Union, places Mexico at the forefront of clean vehicle policy in Latin America and other rapidly growing vehicle markets worldwide. With this, Mexico joins a very short list of countries (U.S., Canada, Japan, European Union, and South Korea) with best-in-class, filter-based standards for heavy-duty vehicles.

The proposed modification of NOM-044-SEMARNAT-20061, published on 17 December in the Diario Oficial de la Federación, 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.

The new standards would require new heavy-duty diesel vehicles sold after 1 January 2018 to meet emissions standards equivalent to those in the United States (EPA 2010) and European Union (Euro VI). 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.