Two weeks after the explosion and fire at the Irving Oil refinery in Saint John, the area where it happened is still a hot zone.

It's off limits and that's holding up the investigation that will determined exactly what happened and why.

Eleven days after the explosion, investigators are 50 feet from the hot zone, taking photos, and analyzing damage from the blast site, but they're still not close enough.

“Until we can get closer and take samples and look at the structure itself, it will be very difficult for us to complete the investigation itself so we're waiting for that,” said Richard Blais, Worksafe NB’s chief compliance officer.

And Worksafe NB is calling in backup.

“We're in the process of hiring some specialists in forensic engineering to help us out as well and we've begun interviewing witnesses which will be part of the evidence that will be collected in order to determine a cause,” said Blais.

In neighbouring Champlain Heights, residents are no longer rattled.

"It gave me a fright,” said resident Norma Manuel. “It shook my house, I shook in the chair and everything, but I just feel everything is handled fine. I'm not scared or nervous or anything like that.”

Paul Gass also feels comfortable.

“This is the community I raised my children in, and there's a lot of young families in here now," he said.

“It doesn't bother me a bit,” said another resident. “It's way over on the other side, they got a good enough fire crew and everything else to take care of that.”

New Brunswick's Department of Environment is currently reviewing the incident report filed by Irving Oil on the refinery explosion.

In an e-mail Irving Oil tells CTV News: “We continue to work with authorities on investigating this incident while providing support to our employees and contractors we are pleased to have safely resumed work on our fall turnaround project and to be returning to normal refining operations on site.”

With files from CTV Atlantic’s Laura Lyall.