Assessment of New Vehicles Emissions Certification Standards in the Metropolitan Area of Mexico City

Abstract

Light duty gasoline vehicles account for most of CO hydrocarbons and NOx emissions at the Metropolitan Area of Mexico City (MAMC). In order to ameliorate air pollution from the beginning of 2001, Tier 1 emission standards became mandatory for all new model year sold in the country. Car manufacturers in Mexico do not guarantee the performance of their exhaust emissions systems for a given mileage. The purpose of this study was to assess whether the Tier 1 vehicles will stand the certification values for at least 162000 km with the regular fuel available at the MAMC. Mileage accumulation and deterioration show that certified carbon monoxide emissions will stand for the useful life of the vehicles but in the case of non-methane hydrocarbons will be shorter by 40%, and nitrogen oxides emissions above the standard will be reached at one third of the accumulated kilometers. The effect of gasoline sulfur content, on the current in use Tier 1 vehicles of the MAMC and the impact on the emissions inventory in year 2010 showed that 31000 extra tons of NOx could be added to the inventory caused by the failure of the vehicles to control this pollutant at the useful life of vehicles.

Management of air pollution in Mexico

“…In 1997, discussions between INE and Mexican Vehicle Manufacturers Association (Asociacion de la Industria Automotriz (AMIA) began to develop further emissions standards closer to those in the USA for introduction in 1999 (Fernandez-Bremauntz, 2008). AMIA disagreed with the new standards, contending that the cost of satisfying them would be excessive and that they would require until at least 2001 or longer to develop air pollution management capacities (Schifter et al, 2006). It suggested that, for a number of reasons, including Mexico City's valley location and altitude, the fuel parameters and the excessive cost of updating air pollution management technologies, it would be challenging at best, and more likely unfeasible at worst, to be able to adhere to the standards by the proposed date of introduction (Schifter et al, 2006).…”

“…AMIA disagreed with the new standards, contending that the cost of satisfying them would be excessive and that they would require until at least 2001 or longer to develop air pollution management capacities (Schifter et al, 2006). It suggested that, for a number of reasons, including Mexico City's valley location and altitude, the fuel parameters and the excessive cost of updating air pollution management technologies, it would be challenging at best, and more likely unfeasible at worst, to be able to adhere to the standards by the proposed date of introduction (Schifter et al, 2006). Further to this, vehicle manufacturers emphasised that Mexico's environmental officials should be more concerned with actions designed to phaseout the use of carburettors in older, less efficient cars, which are responsible for a much higher proportion of air pollution than newer, more modern cars fitted with catalytic converters (Fernandez-Bremauntz, 2008).…”

“…Further to this, vehicle manufacturers emphasised that Mexico's environmental officials should be more concerned with actions designed to phaseout the use of carburettors in older, less efficient cars, which are responsible for a much higher proportion of air pollution than newer, more modern cars fitted with catalytic converters (Fernandez-Bremauntz, 2008). AMIA's antipathy towards introducing the new obligatory standards within the suggested time frame led to INE formulating a new discretionary plan, which involved allowing car manufacturers to elect whether to adhere to the new standards or not (Schifter et al, 2006). The plan offered incentives to participants, such as a two-year break from the government's emissions inspections initiative, a non-elective scheme that necessitates a bi-annual inspection of cars, the first of which must be within the first six months of a car's sale, for cars manufactured in 1999 or 2000 (Fernandez-Bremauntz, 2008).…”

“…In 2001, INE re-opened a dialogue with IAMA about the elective scheme, offering to broaden the scope of the two-year break from the emissions inspections initiative to cover cars manufactured in 2002 and onwards on the proviso that vehicle manufacturers agreed to progressively fit on-board diagnostics systems in their vehicles and to begin adhering to some form of durability standards (Fernandez-Bremauntz, 2008). In 2005, SERMANAT began to roll-out the new standards, which took into account the probable introduction of low-sulphur fuel by the close of the following year, and which was also met with rigid resistance from AMIA (Schifter et al, 2006).…”