Índice Metropolitano de la Calidad del Aire

Calculation process

Categories

• Buena — when the index is between 0 and 50 imecas. The quality of air is considered satisfactory and the air pollution poses minimal or no health risks.
• Regular — when the index is between 51 and 100 imecas. The quality of air is acceptable, however some contaminants could have moderate health effects for a small fraction of the population that has high sensitivity to some contaminants.
• Mala — when the index is between 101 and 150. In this value, some sensitive groups can have health effects. Some people can experience minor symptoms, including people with breathing or heart problems, children and old people. At this stage, there is no significant risk for the general public.
• Muy mala — when the index is between 151 and 200. In this situation everybody can experience negative health effects. Members of sensible groups can present serious issues. This interval activates the phases precontingencia and contingencia fase I of the Programa de Contingencias Ambientales Atmosféricas del Valle de México.
• Extremadamente mala — when the index is more than 201. In this condition the general population may experience very serious symptoms and health effects.