Faced with the increase in pollutants, the Environmental Commission of the Megalopolis (CAMe) maintains the Phase 1 of the ozone contingency in the Metropolitan Zone of the Valley of Mexico (ZMVM), after a day of accumulation of this gas on the surface.
The meteorological conditions have made it difficult for the pollutants to disperse, favoring ozone concentrations that exceeded the 155 parts per billion (ppb) in several stations. If ventilation improves as the models predict, the Restrictions could be relaxed on Thursday from the program Hoy No Circula.
Why Phase 1 was activated and what levels were recorded
The ozone air quality regulations establish a reference limit of 90 ppb in one hour; however, in the ZMVM the CAMe decrees a contingency when the measurements exceed the 155ppbThe recent episode reached levels above that threshold, driven by atmospheric stability, intense radiation, and poor air mixing, a cocktail that favors the formation and accumulation of ozone.
Who is not allowed to circulate during the contingency (Wednesday, March 19)
During Phase 1, between the 05: 00 and 22: 00 hours, extraordinary vehicle restrictions are in place to reduce emissions and exposure. These are the announced measures for this Wednesday:
- Vehicles for private use with hologram 2 will not be able to circulate during the contingency hours.
- Vehicles for private use with hologram 1 whose last license plate digit is 1, 3, 4, 5, 7 or 9, must remain out of circulation.
- Units with hologram 0 and 00, with red sticker and plate termination 3 and 4, are also subject to restriction.
- Vehicles without verification hologram (old, demonstration or transfer, new, with tourist pass, foreign or with plates formed only by letters) will have the same treatment as those of hologram 2.
- It is limited to 50% the circulation of distribution LP gas to stationary tanks that do not have a dry disconnection valve, when the registration number is NOT.
- Cargo vehicles, local or federal, They do not circulate from 06:00 to 10:00, except those enrolled in self-regulation programs of CDMX or EDOMEX.
- Hologram taxis 00, 0, or 1 2 that coincide with the previous assumptions must suspend their circulation 10:00 - 22:00.
Fines for violating restrictions
Skipping the program measures implies economic sanctions of 20 to 30 Measurement and Update Units (UMA). With the value of the UMA in 2025 set at 113.14 pesos, the fine can range from $ 2,262.80 to $ 3,394.20 pesos, in addition to any corresponding immobilizations or remissions.
Health recommendations during the episode
- Avoid civic, cultural and recreational activities, and do not exercise outdoors between the hours of 13:00 and 19:00 hrs..
- Suspend outdoor activities organized by public or private institutions during the same hours.
- Postpone sporting, cultural or mass events scheduled between 13:00 and 19:00 hrs..
- No Smoking, especially in closed spaces.
What could happen in the next few hours
Forecasts indicate a possible gradual improvement in air quality; if confirmed, Restrictions could be lifted on Thursday from Hoy No Circula associated with the contingency. Authorities recommend monitoring official announcements for any changes.
The combination of levels of ozone above 155 ppb, temporary circulation measures and health guidelines define the current operation: the priority is to reduce emissions and exposure while adverse conditions persist, with a view to normalizing mobility if environmental parameters show the expected improvement trend.
