Call for Junking Old Diesel Vehicles

Tehran's struggle with air pollution is exacerbated by old, substandard diesel vehicles that roam the streets of the densely populated city, despite a five-year-old government directive that bans their use in metropolises.

"The directive is yet to be enforced, so these severely polluting vehicles are given free rein," Vahid Hosseini, chief executive of Tehran Air Quality Control Company, was quoted as saying by IRNA. He said over 100,000 diesel vehicles ply the streets of the sprawling capital, most of which do not have diesel particulate filters.

"The directive clearly states that diesel vehicles must at the minimum comply with Euro 4 emission standards and manufacturers are obliged to install DPF filters on these vehicles, but nobody's paying attention," he said.

The official stressed that both domestic and foreign automakers are resisting this directive, which directly impacts the society.

According to recent research, diesel releases 15 times more emissions than gasoline and has serious effects on human health. Criticizing the Ministry of Roads and Urban Development for its role, Hosseini said technical inspection centers that check heavy vehicles, which make up the bulk of diesel vehicles in the city, are managed by the ministry.

"Unfortunately, they only check to see if the trucks and buses meet safety standards and pay no attention to their compliance with environmental regulations," he said.

"Diesel vehicles contribute heavily to PM2.5 concentration in the air, so it is imperative that the ministry takes this seriously." To make matters worse, in most cases, heavy vehicles that do not meet intercity road safety standards end up in cities and are used as school buses and garbage trucks.

"The authorities must start enforcing the directive," he said.

Hosseini noted that TAQCC, which is affiliated to Tehran Municipality, is drawing up a plan that would oblige contractors working with the municipality to ensure their heavy vehicles meet environmental standards.

"Any vehicle older than 20 years cannot be on the streets, yet we see vehicles well over 40 years old in Tehran. This needs to change," he said.

Experts say the three main sources of air pollution in Iran are motorcycle carburetors (a device that blends air and fuel in the engine), diesel cars without filters and gasoline gas guzzlers. They say if 10% of the highly-polluting clunkers are removed from the streets, it will help reduce vehicular pollution by 48%.

There is a global campaign underway to phase out diesel vehicles. Earlier this month, it was reported that Paris, Athens, Madrid and Mexico City are taking action by getting rid of all diesel vehicles by 2025.

Analysts say this is a powerful move in the fight against air pollution and, of course, climate change, and could create a market shift against the production of diesel vehicles.