An inquiry into offshore helicopter safety is scheduled to hear from the lone survivor of the Cougar crash off N.L. in March, Robert Decker, on Thursday. (CBC)

The offshore helicopter safety inquiry in St. John's is preparing for an emotional day of testimony from a crash survivor on Thursday.

The only person to survive the crash of the Cougar helicopter off St. John's in the spring, Robert Decker, is scheduled to tell his story about what happened that day.

A release from the inquiry says special conditions will be put in place for Decker's testimony.

"A significant number of family members of the passengers and crew of Flight 491 have expressed an interest in attending on Nov. 5," the release says.

As a result, inquiry officials are restricting who can be in the room at the time of the testimony.

"While there is space normally reserved for parties with standing in the public hearing room," the release states, "the parties have allocated some of their space to the family members of the passengers and crew. Further, there will not be any space for the general public in the hearing room on that day."

The inquiry urges people to instead watch the testimony live on television or on the internet.

The helicopter carrying 18 offshore workers crashed into the ocean on March 12, about 55 kilometres off the Newfoundland coastline.

Following the crash, the Canada Newfoundland and Labrador Offshore Petroleum Board established an inquiry into offshore helicopter safety.

It is being led by Robert Wells, a retired Supreme Court judge.

Decker has never spoken publicly. However, on the opening day of the inquiry, commission lawyer Anne Fagan indicated what he'd have to say.

"He will describe the weather, the check-in for the flight, the donning of the suits, the preparation briefing and the boarding of the helicopter and flight out," she said. "He will describe the flight back towards land, the crash of the helicopter into the ocean, his escape, and ascent to the surface. Mr. Decker will explain how the cold water affected his ability to access features of the survival suit, such as the gloves, face hood and flotation collar."

Fagan said Decker, who was 27 at the time of the crash, will describe how he was hoisted from the water by a Cougar search-and-rescue helicopter. He will also talk about his injuries and his recuperation.

"Mr. Decker is still recovering, and although this will be difficult for him, he believes it's important to provide the inquiry and the public, especially the families, with this information."