Last week's deadly helicopter crash off Newfoundland has renewed discussion about the effectiveness of safety measures in the offshore oil industry.

One person survived and 17 others were killed last Thursday when a Cougar Helicopters aircraft crashed into the ocean about 65 kilometres southeast of St. John's. The helicopter had been taking workers to offshore oil platforms when it went down.

While safety measures in the industry have increased dramatically since the 1982 Ocean Ranger disaster, experts caution survival suits and intensive training offer no guarantees.

John Swain, the chief executive officer of Halifax-based Survival Training Systems, said every offshore worker receives basic survival training and survival suits.

Part of the training includes helicopter disasters, he said.

"There's one day alone on a five-day basic survival course that deals with helicopter emergencies," he said. "That goes right into practical underwater escape from a helicopter which would be the most untoward, severe situation one would face."

However, the suits and training are most helpful in controlled or soft landings, which give workers time to exit the aircraft and climb aboard a life raft.

Company president Peter Gibbs said the roughly six-kilometre debris field around the crash site suggests it wasn't a controlled landing.

"Whatever happened, it happened suddenly and there was probably a lack of control on the aircraft as it went into the water."

Searchers initially said they didn't receive any signals from emergency beacons in the survival suits of the helicopter passengers.

On the weekend, however, officials said two beacons did work. They belonged to the lone survivor, Robert Decker, and Allison Maher, whose body was found on the surface of the ocean. It's not known how Decker and Maher wound up outside the helicopter.

Experts believe the absence of other signals indicates the beacons were submerged deep under water. Searchers are removing the remaining bodies from the wreckage of the helicopter, which is resting on the sea floor.

The deaths of 84 people when the Ocean Ranger sank 27 years ago led to major changes within the offshore industry.

More than 100 metres high and as long as two football fields, the oil rig sank during a fierce storm off the coast of Newfoundland.

A Royal Commission concluded the workers didn't have proper safety training or survival suits. The probe led to safety changes within the offshore industry, including two safety suits for each worker and strict enforcement of safety regulations.

However, former chief justice Alex Hickman, who headed the inquiry, questioned Monday whether all of his recommendations were implemented.

Hickman said there should be a dedicated search and rescue helicopter in St. John's, complete with fully trained crew ready to depart on short notice.