The family of the crane operator who was severely injured when a Kingston, Ont. student housing complex went up in flames has thanked the rescue team that came to his aid.

In a public letter released Thursday, Tom Jastrzebski described his father, Adam Jastrzebski, as a "brave man whose actions saved his life."

"Our family sincerely thanks all those involved in his rescue and the medical professionals who are assisting with his recovery," Tom Jastrzebski wrote.

Adam Jastrzebski remains at Kingston General Hospital, where his condition was recently upgraded from stable to good.

After the fire broke out beneath him at the construction site on Tuesday afternoon, Jastrzebski managed to escape the cab and crawl across the towering crane where he waited for an hour before a military chopper picked him up.

His employer, Aram Malek of Canadian Professional Crane Inc., told reporters on Wednesday that the 68-year-old veteran crane operator suffered severe burns.

Fire officials in Kingston believe that the temperature reached an estimated 1,000 C during the blaze.

"He's in pain," Malek said. “Everything burned … There was nowhere to run. The only way to run was away from the fire.”

After the ordeal, Jastrzebski told a Kingston newspaper that he will no longer work on construction cranes.

The crane remains at the scene of the fire, but engineering officials have raised concerns that it could be on the verge of collapsing.

Kingston Fire Chief Rheaume Chaput said Wednesday that if the structure is stable enough, engineers will dismantle it and remove it from the site.

The fire forced an evacuation order of homes surrounding the five-storey apartment building that was under construction.

City officials have said the evacuation order will remain in place until the crane is removed from the scene.

The cause of the fire has not been determined.