``All the three engine types, being used by the company to produce heavy and light commercial vehicles, have already been engineered to meet Euro-I emission norms,'' R Seshasayee, managing director, Ashok Leyland told PTI here.

Leyland produces three engine categories for meeting the needs of its various kinds of vehicles. While the `Hino' range of engines are produced for heavy buses, `Iveco' engine technology is being used for its `Cargo' range of light commercial vehicles.

The company also offers buses running on compressed natural gas (CNG) which is more eco-friendly than petrol and diesel, he said.

Ashok Leyland has supplied 10 CNG-based buses to Bombay Electric Supply and Transport (BEST) which are running successfully for over a year, Seshasayeesaid.

Meanwhile, Leyland sources indicated that there could be a 10 per cent increase in vehicle costs due to meeting the Euro-I emission standards.

Ashok Leyland has also offered to supply CNG buses to the Delhi government for enabling the latter to replace its existing fleet by more environment friendly vehicles by April 1, 2001, the deadline set by the Supreme Court, he said.

``CNG engines would entail an additional cost of Rs 3.5 lakh per unit. We have offered to the delhi government to supply new cng buses and also convert the existing ones,'' Seshasayee said.

According to the Supreme Court directive of July 28 last year, the Delhi transport department has to acquire 10,000 buses running on the green fuel CNG before April 1, 2001, he said.

The Delhi government had recently invited tenders for CNG buses in a bid to meet the deadline. Leyland has also applied in response to the tender and expects to get a positve response.

``We are hopeful of getting the contract, as we believe that our bidprice is the lowest,'' he said.

CNG is considered to be a safe and green fuel and mainly consists of methane, which has more hydrogen molecules for every carbon molecule.

``Being lighter than air, it dispenses easily and does not form sufficiently rich mixture for combustion to take place. Due to this very nature, CNG is preferred to liquified petroleum gas (LPG) and petrol,'' he said.

Seshasayee said CNG also brings down carbon monoxide, hydrocarbons and nitrogen oxides emissions.

At present, there are about 10 CNG filling stations in Delhi. The Government plans to set up more CNG centres here to provide sufficient availability of the gas for vehicles.

Ashok Leyland closed the fiscal 1998-99 by recording a 6.63 per cent drop in sales at 29,458 vehicles as compared to 31,547 units sold in the previous year.

In the medium duty vehicle segment, the company reported sales of 26,817 vehicles during the fiscal ended March 1999, a decline of 5.4 per cent from last year's figure of 28,355 vehicles.

Theexports from the company, however, grew marginally during 1998-99 to 2,168 vehicles from the previous year's figure of 2,148.

Ashok Leyland, the largest manufacturer of commercial vehicles in India, attributed the drop in sales to recession affecting various sectors of the economy.