Metro Manila Residents, Check the Air Quality in Your City Through This DENR Site

(SPOT.ph) Can't figure out if it's haze or smog that's blocking your view here in Metro Manila? In case you don't know, the Department of Environment and Natural Resources (DENR) has a website that specifically monitors the air quality in your area so you would know if it's time to mask up or not.

Also read:
Fog, Smog, or Vog? Here's What's Causing Gloomy Metro Manila Skies, Says Phivolcs
Taal Vog, Mayon Ash Flow: What You Need to Know

What's in the DENR's Ambient Air Quality Monitoring site

The website shows the updated air quality in Metro Manila and beyond.

As of 1 p.m. September 26, air quality is "good" in Caloocan, Makati, Parañaque, Pateros, San Juan, and Taguig. Mandaluyong's air quality is "fair". This monitoring site measures both PM10 and PM2.5 (particulate matter, more on that below.)

Conditions have improved after the smog last Friday, which was initially attributed due to the volcanic smog (vog) over Taal Volcano some 90 kilometers away in Batangas.

"Nitong mga nakaraang linggo grabe ang traffic dahil sa pagdami ng mga sasakyan at mga activities at laging umuulan so damp ang condition so nagkakaroon tayo ng thermal inversion in terms of atmospheric conditions," DENR Assistant Secretary Gilbert Gonzales told TeleRadyo Serbisyo.

Ideally, all cities in the National Capital Region have monitoring stations, but the website showed Quezon City and Valenzuela have "no station" while the stations in Las Piñas, Malabon, Manila, Marikina, Muntinlupa, Navotas, Pasay, and Pasig are offline.

Some cities have outdated equipment while some need recalibration which can be solved if there's enough budget for it, said Gonzales.

Understanding DENR's Ambient Air Quality Monitoring site

Air quality is measured with the Air Quality Index (AQI), which is like a thermometer that measures from zero—lowest or safest—to 500, the highest and most dangerous. It also monitors the concentration of particles in the air, or particulate matter (PM) specifically PM10 (bigger particles) and PM2.5 (smaller particles).

PM10 AQI, found on the left side of the DENR website, measures the bigger particles which can irritate the nose, eyes, and throat. PM10 particles are usually dust from roads, farms, dry riverbeds, construction sites, and mines, according to the U.S. Center for Disease Control and Prevention. The one found on the right is for the PM2.5—the smaller, finer particles that are more dangerous as it can enter the deep parts of your lungs, or even your blood. This usually comes from smoke from fires and emissions from power plants, industrial facilities, and cars and trucks, U.S. CDC said.

The website is color-coded, making it easier to understand.

• Green - Good (0-50 AQI Value)
• Yellow - Fair (50-100 AQI Value)
• Orange - Unhealthy for sensitive groups (101-150 AQI Value)
• Red - Very Unhealthy (151-200 AQI Value)
• Purple - Acutely Unhealthy (201-300 AQI Value)
• Maroon - Emergency (301-500 AQI Value)

What to do when particle pollution levels are high

Once AQI value reaches 101, start limiting exposure and stay indoors. Here are some tips from U.S. CDC and U.S. Environmental Protection Agency:

• Avoid exercising or working outdoors for long periods of time
• Choose less strenuous outdoor activities so you won't breathe in outdoor air as much
• Avoid exercising near busy roads where PM is worse because of vehicular emissions
• Postpone outdoor recreational activities
• Avoid sources of particles indoors like wood-burning stoves, fireplaces, and candles