Air quality has been worsening in most major Vietnamese cities; and in recent times, Ho Chi Minh City has repeatedly made it to the top offenders in the world.

Since 2012, many studies have concluded that traffic was responsible for 60-70 percent of the air pollution in major cities, including HCMC.

The biggest city in Vietnam has around 7.4 million motorbikes and those that have been in use for more than 10 years account for 68 percent of the total. The carbon monoxide and hydrocarbon, both harmful to humans, that is emitted from motorbikes account for 90 percent of the total emitted by all motor vehicles operating in the city, HCMC Transport Department deputy director Bui Hoa An told VnExpress.

"From these figures, it can be said that motorbike pollution in HCMC is at an alarming level," An said.

He was explaining the need for a pilot program to check motorbikes emissions that his department is preparing in cooperation with the Vietnam Association of Motorcycle Manufacturers (VAMM) and the Institute of Transport Science and Technology under the Ministry of Transport.

The central government had already green lighted a pilot project to control motorbike emissions in 2010. It would be implemented first in Hanoi and HCMC from 2010 to 2013 before being expanded to other localities.

However, that project has remained on paper until now, basically because it lacked a legal framework.

Regulations on periodic emission inspections for motorbikes are not included in the Law on Road Traffic, making it difficult to put the plan into practice, An said.

Then, in December last year, Prime Minister Nguyen Xuan Phuc approved the national road traffic safety plan for the 2021-2030 period with vision until 2045. This plan targets the removal of all expired and illegally-modified motorbikes from the nation’s roads.

To implement this plan, the Ministry of Transport has been assigned to collaborate with related agencies and local authorities in cities and provinces to check emissions of motorbikes periodically until 2025.

That is an important premise for developing a legal framework for motorbike emission control in HCMC, An said.

Under the new pilot program, the city will be able to cut the emission of more than 56,000 tons of carbon monoxide and 4,400 tons of hydrocarbon per year.

The cost of setting up the testing system and hiring staff for the program is estimated at VND553 billion ($24 million) from now until 2023. After this period, fees and fines will start covering the program cost, An said.

The city will first build 88 inspection centers within this year and roll out regulations to test vehicles.

In the next two years (2022-2023), testing will become mandatory. The testing fee is likely to be VND50,000 ($2.16) per vehicle, but this might not be collected from poor people.

Motorbikes owned by residents of downtown districts 1, 3 and 5 that fail to meet emission standards will be fined.

In 2024 and 2025, another 78 testing centers will be built, and the fines will be extended to districts 10 and Tan Binh.

In 2026, districts 4, 6, 8, 11, Tan Phu, Binh Thanh, Phu Nhuan and Go Vap will also be covered.

In May last year, the department had collaborated with the VAMM to trial the program, checking motorbikes for emissions in 1, 3, Phu Nhuan, and Tan Binh districts.

More than 10,600 motorbikes were checked, and most of the vehicles older than five years failed to meet emission standards.

Apart from reducing pollution, the program is expected to ensure traffic safety via periodical maintenance and checking.

The division of zones to apply emission control measures will also contribute to reducing traffic congestion, especially in the central area because only "qualified" vehicles will be allowed to enter it, An said.

Commenting on the program, Do Van Chung, deputy head of the Binh Tan District urban management office, had said last year that it would disproportionately burden the poor since most of them drive used motorbikes.

With several million motorbikes in the city, a few hundred inspection centers would be inadequate, he added.

An said that the program will consider supporting policies such as offering free inspections for the poor and those with low income as well as helping them buy new vehicles at preferential prices.