New Delhi, Mar 12 (IANS): Rampant flouting of standard norms for CNG kits and its purchase from unauthorised dealers are the two of the many reasons that make CNG vehicles dangerous to drive, a Delhi Transport Department Officer said, here on Monday.

Special Commissioner of Delhi Transport Department (Operations) K.K. Dahiya was referring to the tragic incident on SUnday in which a mother and her two little daughters were charred to death, when their CNG-fitted car burst into flames in East Delhi.

The mishap was the second this year, after a compressed natural gas (CNG) auto exploded in South Delhi's Sadiq Nagar on February 22 killing its driver.

Speaking to IANS about incidents of blasts in CNG-driven vehicles, he highlighted the predilection of vehicle owners to cut corners by getting shoddy CNG kits installed through unauthorised dealers in Meerut and Ghaziabad in UP and Gurugram in Haryana.

In Delhi, such untested and, thus unapproved, kits are procured from vendors in the Mayapuri scrap market and Kashmiri Gate.

"Manufacturers and distributors of CNG fuel kits are required to upload details of the kits sold on the NIC software, from where we swiftly detect cases of unapproved or uncertified kits," Dahiya told IANS.

"Unapproved CNG dealers in Delhi have contacts with dealers in the adjoining states. They get CNG kits installed cheaper than the market price.

"They get a vehicle's registration certificate transferred to another state's Transport Department and then install a local CNG kit by using a low quality, used cylinder, procuring documents through unfair means," automobile expert Abdul Wahjid told IANS.

"The second cause of fire in CNG vehicles is owners skipping the mandatory lab test for a CNG cylinder every three years. It is done to check the cylinder's capacity to withstand pressure and prevent it from exploding while filling gas at stations," another automobile expert Tutu Dhawan told IANS.

"The lab test means the CNG cylinder carries its silver-coloured report plate with the test date, which the filling station staff can check before every refill," Dhawan said.

Filling stations are instructed not to fill CNG in vehicles with expired cylinder plates, but some in Delhi, UP and Haryana flout this rule for money," Dhawan said.

Dahiya added some owners even manage to get updated cylinder plates, illegally for Rs 100-200.

"The other and more severe for such fires are short-circuit in vehicle battery, low and roadside maintenance from uncertified mechanics, break down of fuse, not changing of spark plug cables.

"Cars nowadays are manufactured with 50 per cent metal and 50 per cent synthetic fibre, rubber and other inflammable materials, which only contribute to the spread of fire," Dahiya said.

"The CNG gas is not inflammable and does not ignite itself. It is a light gas. It only flames up only when you direct it to fire," he said.