How Does a Water Pipe Explode?
There’s a depressingly long list of accidents, many fatal, resulting from contractors puncturing buried gas pipes after failing to properly locate them prior to excavating, but what about a fatal gas explosion during excavations without any gas pipe being ruptured? That’s what happened in New Zealand.
Canadian Pacific, the company carrying out the work under contract to Auckland Council body Watercare Services was fined $NZ55,250 as a result of the explosion, which took place in 2011. Watercare Services was fined $NZ81,000. Others paid a much higher price. Watercare Services employee Philomen Gulland lost her life, engineer Ian Winson lost both legs and another five workers suffered a range of injuries that included. fractures, head wounds, lacerations, puncture wounds and post-traumatic stress disorder.
So what happened? Canadian Pacific had been contracted by Watercare Services to repair a leaky valve chamber on a water pipe, which had been drained while the system was being upgraded.
While the valve was being repaired, four Watercare inspectors, including Gulland and Winson, entered the pipe 500 metres from where Canadian Pacific was working. Their personal gas alarms sounded, the group exited the pipe and used a fan to ventilate it. Gulland and Winson then re-entered the pipe and it exploded.
Gas had been sucked into the pipe from a nearby gas pipeline when the water main was drained. A Watercare Services spokesman was reported saying such an event “appear[s] to be unprecedented in the water industry anywhere in the world.”
The company pleaded guilty to a charge of failing to take all practicable steps to ensure the safety of its employees and to a charge of failing to take all practicable steps to ensure the safety of its contractor’s employees. It was fined $NZ81,000 and ordered to pay $NZ315,000 reparation costs.
Canadian Pacific claimed that nothing could have been done to prevent the accident. However it was found guilty of failing to apply for a permit for the introduction of a flame into an explosive environment and of failing to follow Watercare Services’ procedures, which required monitoring for explosive gas.
PelicanCorp’s technology and service suite has been designed and built around the network and asset design and construction processes. Civil contractors operating in the ‘before you dig’ sector, use PelicanCorp’s services to locate and protect the essential infrastructure of public and private sector organisations including those providing telecommunications, power, water and other services. PelicanCorp operates in Australia, New Zealand, UK, North America, Europe and Singapore. It was established in 2000 and is headquartered in Melbourne, Australia.
For further information please visit www.pelicancorp.com