THE Department of Environment and Natural Resources (DENR)-Environmental Management Bureau (EMB) in Davao Region reported that the air quality in Davao City has improved after the local government unit implemented a community quarantine.
Melvin Dapitanon, head of the Ambient Air Quality Monitoring Unit of DENR-EMB-Davao, told SunStar Davao Monday, March 30, that based on their two automatic monitoring systems, since March 21, there was a 20 to 30 percent decrease in particulate matter (PM) 10 and PM 2.5.
The community quarantine in Davao City took effect on March 19.
EMB's monitoring systems are located at the Francisco Bangoy International Airport (Davao Airport) and Calinan National High School.
PM 2.5 is a fine mixture of minute solid particles and liquid droplets present in the atmosphere emitted from power plants, industries and vehicles react in the air.
PM 10, on the other hand, is typically from emissions of crushing and grinding machines and dust from cemented and dirt roads.
"Air quality improved which attributed to the effects of Covid-19 measures," Dapitanon said.
He added that the three major air pollutants in the city are mobile sources; stationary sources (power and cement plants, industries); and area sources (cooking using fuel, unpaved road, construction, etc.).
The reduction of vehicles on the streets and less human activities have significantly contributed to the reduction of air contaminants, paving the way for cleaner air.
Interfacing Development Interventions for Sustainability (Idis) welcomed the improvement in the air quality of the city.
"We 'Better air quality' with Covid-19 measures
appreciate that there is a significant decrease of pollutants in our air monitoring. As per observation, we have less smog and clearer skies when viewing the city at these times, plus supported by the data collected by DENR's air quality monitoring stations depicting lower particulate matter (PM 2.5 and PM 10) as compared from February and early March. Reflectively, a photo-chemical smog consists of suspended particulates," Lemuel Manalo, environmental planner and Idis environmental research specialist, said in an online message to SunStar Davao.
Manalo pointed out that once Covid-19 fizzles out, the city can implement measures that will allow it to sustain the improved air quality.
"We can sustain being clean-air and smog-free city by passing a car-free day policy just like the car-free day in Jakarta, Indonesia," Manalo said.
Other measures to maintain the air quality include improving mass transportation, strict monitoring of emissions and treatment of pollutants, more monitoring stations and public info boards on air quality index, and mainstream non-motorized practices such e-bikes, bicycles, trisikad, skateboards, etc.
"We need to sustain the decrease and being smog-free even after Covid-19 quarantine period," Manalo said.
DENR-EMB-Davao said air quality index in the city remains at good level and poses no health concerns. (With reports from Ralph Lawrence Llemit)