Authorities have extended the environmental pre-emergency in the Metropolitan Region through Monday, June 9, following continued poor air quality and unfavorable weather conditions in the Santiago basin.
The alert, declared Sunday for the first time this year, was prompted by elevated levels of fine particulate matter (PM2.5) recorded at the Cerro Navia monitoring station, according to the Metropolitan Regional Presidential Delegation. These particles, less than 2.5 micrometers in diameter—roughly 20 times smaller than a human hair—can penetrate deep into the lungs and pose serious health risks.
The spike in pollution was attributed to increased emissions from wood-burning heaters, industrial activity, and vehicle traffic, with concentrations rising notably after 8 p.m. Saturday.
The Chilean Meteorological Directorate (DMC) forecasts surface cyclonic circulation and an upper-level ridge for Monday, with temperatures ranging from 3°C to 22°C. No air mass movement is expected to ventilate the basin, exacerbating smog accumulation.
Restrictions and Mitigation Measures
In response, officials have implemented a series of restrictions aimed at reducing emissions:
- Wood-burning stoves and heaters are banned in Santiago Province, as well as in the municipalities of San Bernardo and Puente Alto.
- Pellet stoves are prohibited throughout the Metropolitan Region.
- Agricultural burning remains banned through October 31, with enforcement by the Agricultural and Livestock Service (SAG) and the National Forestry Corporation (CONAF).
- Industrial operations at 60 large stationary sources must be suspended, as outlined by the Environmental Superintendency.
The Ministry of Education has advised schools to adjust the intensity of physical education activities rather than cancel them. Recommendations include focusing on low-exertion exercises conducted indoors to minimize health risks for students.
Vehicle Restrictions
To curb vehicular emissions, the following traffic restrictions will be enforced from 7:30 a.m. to 9:00 p.m. on Monday:
- Vehicles without a green seal (pre-2002): All license plates are restricted within the Américo Vespucio ring and in the municipalities of San Bernardo, Puente Alto, and across Santiago Province.
- Green seal vehicles (registered before Sept. 1, 2011): Plates ending in 6 and 7 face restrictions in Santiago Province, San Bernardo, and Puente Alto.
- Motorcycles registered before Sept. 1, 2010: Plates ending in 6 and 7 are also restricted in the same areas.
Additional restrictions apply to commercial and public transportation:
- Private, intercity, and rural buses without a green seal: Plates ending in 2-3-4-5-6-7 are restricted from 10 a.m. to 4 p.m. in Santiago Province, San Bernardo, and Puente Alto.
- Cargo vehicles without a green seal: Plates ending in 2-3-4-5-6-7 are restricted within the Américo Vespucio ring from 10 a.m. to 6 p.m.
- Green seal cargo vehicles and pickup trucks: Plates ending in 2 and 3 are subject to the same time restrictions.
Officials urge residents to comply with the measures to protect public health and help reduce pollutant levels. Further updates will be provided as conditions evolve.
