The exponential growth of vehicles over the last decade has forced Bangladesh’s authorities to set new transport emission standards to curb increasing air pollution, in a country of more than two million vehicles and little effective monitoring.
The Department of Environment (DoE) has devised separate emission standards for vehicles powered by diesel, petrol and compressed natural gas (CNG), partly in line with its 2012 study on air pollution by the transport sector.
On May 2, environment minister Anwar Hossain informed parliament of the revision to the 2005 vehicular emission standard but did not disclose details of them to the cabinet. Instead, he said that the standards were in the “process of approval”, without setting any timeframe.
“[The] reduction of pollutants from vehicles run by petrol and diesel will improve air quality in Dhaka and other parts of Bangladesh,” Monjurul Hannan Khan, director of the DoE’s clear air and sustainable environment (Case) project, told thethirdpole.net.
In 2005, for the first time, the government set detailed and comprehensive emission standards to improve air quality in Bangladesh. The standards allowed a petrol-run vehicle to emit 4.5 per cent carbon monoxide and 1,200 parts per million (ppm) of hydrocarbon.
“In our new proposal, we have reset emissions of carbon monoxide for a petrol-run vehicle at 0.5 per cent,” says Rezwan Hayat, deputy director of the Case project. “This is a big cut proposal, but we have not changed the level of emissions of hydrocarbon.”
New emission standards for diesel-run vehicles are recommended at 60 Hartridge Smoke Units (HSU) for turbocharged vehicles and 50 HSU for those that are not turbo charged, instead of 65 HSU set in the 2005 standard. The proposed emissions for vehicles running on CNG remain unchanged at 3 per cent. Hartridge Smoke Units are used to measure the opacity of exhaust gases, especially from diesel engines.
The 2012 study
The number of vehicles in Bangladesh has grown by almost 135 per cent since 2003, according to the DoE’s 2012 study. There are more than two million vehicles and one million petrol-run motorcycles in use, says Shitangshu Shekhar Biswas, director of the Bangladesh Road Transport Authority (BRTA). Of these, 290,000 are CNG-fuelled vehicles, according to the state-owned Rupantarita Prakritik gas company which supervises the conversion of vehicles to run on CNG.
In 2012, vehicles were the second largest air polluter after brick kilns, but the study predicted that vehicles would soon claim the top spot. In addition, some 80 per cent of petrol-run motorcycles failed the inspection test carried out during the study.
The government could enforce new standards for petrol-run vehicles “but the main problem lies with diesel-run vehicles”, says Professor Mohammed Ehsan, a teacher of mechanical engineering at the Bangladesh University of Engineering and Technology. “Most of these are commercial vehicles [that are]not maintained properly, thus causing huge air pollution.”
A second problem is the adulteration of diesel and petrol.
“Currently, sulphur content in imported diesel is 500 ppm,” says Ehsan. A decade ago it was several thousand ppm. “But the problem is that unscrupulous traders mix various impurities with the diesel and petrol, so vehicles using these adulterated fuels spew out more pollutants.”
New laws must be strictly implemented to be useful, which is currently not the case, added Ehsan.
Will the new emission standard work?
Up to 12 per cent of Bangladesh’s urban population had asthma in 2002, according to a study by Orion Pharmaceuticals Limited from the same year. Air pollution was given as one of the main causes, and was also attributed to other pulmonary conditions which have a huge toll on the health of the urban population.
Amid clamour from environmental groups, civil society leaders and the media, the government phased out more than 40,000 polluting two-stroke baby taxis and introduced a CNG-fuelled three-wheeler. This improved the air quality substantially, clearing the hazy air, but pollution from petrol and diesel-run vehicles continued.
While the government set the first vehicular emission standards in 2005, the proper facilities to enforce them were not available. “Every year, we issue fitness certificates to all vehicles from 76 offices dotted across the country, but unfortunately we have no equipment to examine vehicular emission in 75 [of the 76]offices,” Biswas told thethirdpole.net, adding that the only BRTA office equipped with emission test facilities is in Dhaka’s Mirpur district.