Mexico: Air Quality Standards

Overview

 * Standard type: Ambient air quality standard
 * Regulatory agency: Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT) - Secretary of the Environment and Natural Resources
 * Current standard: Normas Mexicanas de Calidad del Aire (Mexican Air Quality Standards) - six standards regulating eight criteria pollutants
 * Applicability: Nationwide

History
Air quality legislation has been in place in Mexico since the 1970s, and current ambient air quality at the federal level is regulated by Mexico's environmental and natural resources ministry, Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT). In 1993, SEMARNAT issued a series of official Mexican standards, or normas (NOM), that regulate maximum concentrations of environmental contaminants. These include 8 criteria pollutants: CO, O3, NO2, SO2, PM2.5, PM10, Total Suspended Particulate Matter (TSP), and lead (Pb).

Mexico's ecology and climate change institute, Instituto Nacional de Ecologia y Cambio Climatico (INECC), which functions as the research arm of SEMARNET, monitors air quality across the country via 15 monitoring stations.

Technical Standards
Carbon monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone (O3), particulate pollution (PM2.5, PM10, and TSP), and sulfur dioxide (SO2) are the criteria pollutants regulated in Mexico.

Current limit values are presented in the following table.

Regulatory Documents

 * Ozone - NOM-020-SSA1-1993
 * Carbon monoxide - NOM-021-SSA1-1993
 * Sulfur dioxide - NOM-022-SSA1-1993
 * Nitrogen dioxide - NOM-023-SSA1-1993
 * Particle pollution - NOM-025-SSA1-1993
 * Lead - NOM-026-SSA1-1993