Circulation of poor-quality cooking gas cylinders has emerged as a big threat to the lives of the general public.

At least four people were killed while several sustained injuries in recent incidents of cylinder explosion in the Capital.

Three individuals lost their lives when a cylinder supplied by HP Gas exploded at a metal workshop in Haugal, Lalitpur on May 20. In a separate incident, one died and six others were injured after a cylinder supplied by Sugam Gas leaked and caught fire at Samajhdari Marg of Kalimati last Tuesday.

Chandra Thapa, general secretary of Gas Dealers’ Federation Nepal, around 2-3 percent of the gas cylinders supplied by the bottlers are defective. Given the fact that there are 6.5 million cylinders from 53 bottlers in circulation in the country, around 200,000 gas cylinders could be defective.

“Of late, the number of cylinders with defects in the valves is on the rise,” said Thapa, adding the negligence has led to an increasing number of accidents.

Negligence of bottlers, lack of awareness among consumers and poor government monitoring have been blamed for the accidents.

According to the gas dealers, there are a large number of old cylinders stocked with the bottlers. Although the bottlers are supposed to destroy old and defective ones, they have not been doing so.

Thapa suggested that use of rubber pipes, distribution only through certified dealers, holding campaigns to raise consumer awareness and timely testing of the cylinders could help prevent such incidents.

Besides those supplied by three domestic cylinder manufacturers — Nepal Cylinder of Amlekhgunj, Aerotech of Bara and Griha Laxmi Metals of Chitwan — bottlers also use cylinders imported from India.

The bottlers have to acquire Nepal Standard certification from Nepal Bureau of Standards and Metrology (NBSM) for their cylinders. They have to mandatorily carry out hydrostatic testing — for the first time in 10 years and then every five years — in presence of NBSM representatives. However, most of the bottlers have failed to do so, according to NBSM.

According to Nepal Oil Corporation (NOC), the bottlers have destroyed just 23,319 defective cylinders in the last 47 years. “Although gas companies need to report to the NOC each time they destroy defective cylinders, only a few companies have been doing so,” said an NOC official.

The official said although the life of a cylinder is not definite, “the bottlers have to destroy the cylinders immediately if they are old, have scratches or they leak”.

NBSM has also failed implement safety standards for liquefied petroleum gas (LPG) cylinders.

According to a report, a whopping 30 percent of the LPG cylinders in circulation are prone to explosion either due to poor quality or deposition of sludge.