The Department of Environment and Natural Resources–Environmental Management Bureau (DENR-EMB) has reported a general improvement in the country’s air quality in 2024.

DENR-EMB said this progress is attributed to sustained efforts to reduce vehicular emissions, complemented by strengthened industrial emission controls and enhanced air quality monitoring under the midterm administration of President Ferdinand Marcos, Jr.

Based on EMB monitoring for CY 2024, the air quality in Metro Manila has shown notable improvement in terms of Particulate Matter 10 (PM10) concentration by 17.4 percent.

Following the implementation of Euro 4 fuel and emission standards in 2016, the average concentration of PM10 in Metro Manila dropped from 46 micrograms per normal cubic meter (µg/ncm) in 2016 to 38 µg/ncm in 2024.

Nationwide, the PM10 average also decreased by 28.2 percent from 39 µg/ncm in 2016 to 28 µg/ncm in 2024. These figures are well below the maximum acceptable levels under the national air quality guideline value for PM10, which is 60 µg/ncm.

Metro Manila also recorded improvements by 37.6 percent in PM2.5 levels, which averaged 27 µg/ncm in 2016, falling to 16.86 µg/ncm in 2024. On a national scale, PM2.5 levels decreased from 20 µg/ncm in 2016 to 16 µg/ncm in 2024, reflecting the effectiveness of current emission reduction initiatives. The acceptable annual air quality guideline value for PM2.5 is 25 µg/ncm.

Particulate matter consists of microscopic solid or liquid particles suspended in the air, commonly originating from vehicle exhaust, burning of fossil fuels, industrial processes, road construction, and agricultural activities. PM10 refers to particles 10 micrometers or smaller, while PM2.5 includes finer particles with diameters of 2.5 micrometers or less. These smaller particles pose a higher health risk because they can penetrate deeper into the lungs and even enter the bloodstream.

The DENR said these achievements are in line with the goals outlined in the Philippine Development Plan, specifically under the objective of establishing livable communities through improved environmental quality.

In 2024, 65 percent, or 22 out of 34 highly urbanized and major urban centers, were within the ambient air quality guideline values for both PM10 and PM2.5, surpassing the national target of 62 percent.

Recognizing that mobile sources, including motor vehicles, remain the leading contributor to air pollution, the EMB has intensified its initiatives to reduce vehicular emissions. From 2022 to 2024, the Bureau issued a total of 1,807 Certificates of Conformity (COC) for Euro IV-compliant vehicles. These certifications ensure that new vehicles meet stringent emissions requirements before entering the market.

Euro IV, or Euro 4, emission standards regulate the maximum allowable levels of pollutants emitted by motor vehicles, particularly light-duty and heavy-duty types. These standards were introduced to significantly limit emissions of nitrogen oxides (NOx), particulate matter (PM), carbon monoxide (CO), and hydrocarbons (HC), which are known to contribute to air pollution and respiratory illnesses.

In the industrial sector, the EMB has been implementing the Industrial Emission Monitoring Program to oversee compliance among major pollution sources, such as coal-fired power plants and cement manufacturing facilities. The Bureau has accredited 20 firms with 57 stack sampling teams as of June 2024 and 20 firms with 59 stack sampling teams as of June 2025. Third-party emission testing firms and facilities equipped with Continuous Emission Monitoring Systems (CEMS) connected to the EMB Data Center enable real-time emissions tracking and ensure regulatory compliance.

As of 2024, the EMB operates and maintains 113 Air Quality Monitoring Stations across the country to further strengthen air quality management. These stations provide essential real-time data on harmful air pollutants, which is the basis for air quality assessments and policy decisions.

During volcanic eruptions and haze events, the EMB also issues a Daily Air Quality Bulletin in coordination with the National Disaster Risk Reduction and Management Council (NDRRMC), allowing local government units and communities to prepare and respond effectively.

The EMB is now actively leading the transition toward Euro V fuels and engines, which is expected to reduce particulate matter emissions by up to 95.5%. The Bureau is also working to amend and strengthen existing industrial emission standards under Republic Act No. 8749, or the Philippine Clean Air Act, with a focus on regulating emissions of particulate matter, carbon monoxide, nitrogen oxides, and sulfur oxides from industrial sources.