The National Air Quality Information System (Sinca) in Chile defines air quality through five distinct phases. These phases range from “good” to “emergency,” providing a tiered assessment of pollution levels. As of September 6, 2026, air quality data is being monitored in Quilicura, Chile, utilizing this Sinca system. The phases allow for a clear understanding of the current air state and potential health risks. “Regular,” “alert,” and “pre-emergency” represent escalating concerns requiring increased attention. The final “emergency” phase signals critical pollution levels demanding immediate action to protect public health in Quilicura. This tiered system is crucial for informing residents and authorities about air quality conditions.