SOMBA K'E/YELLOWKNIFE - The evacuation of Centre Square Mall and the Yellowknife Inn on Wednesday afternoon was thanks to a missed propane delivery to the A&W restaurant, according to Yellowknife Inn general manager Derek Carmody.

The smell of propane was pungent outside the Centre Square Mall on Wednesday, leading some people to cover their noses. - Charlotte Hilling/NNSL photo

For reasons yet to be determined the tanks were not filled, leading to a "burp" of methyl mercaptan – the odour added to propane so people will notice if there is a leak.

Deputy fire chief, Darcy Hernblad said this not a strange occurrence.

"It's not unusual for a tank, when it's empty, to let out a little bit of a hiccup or burp," he said.

Carmody said about 80 people had to be evacuated from the Yellowknife Inn as well an indeterminate number of people from the lower mall level, and added this was the first time an empty propane tank had lead to an evacuation.

Hernblad said a member of the public reported smelling gas outside the Yellowknife Inn, and the call went out to the Yellowknife Fire Division around noon.

It took about 25 minutes for firefighters to determine the origin of the smell, using an electronic device that detects locations where an explosion may be imminent.

Hernblad said the the Fire Division commonly responded to suspected propane leaks, and treated the issue seriously.

"The reason we treat these as a code three emergency is because a lot of the time we have bona fide leaking propane tanks," he said.

Diane Wiseman, who works at Main Street Cafe in the mall, said she knew about A and W's low propane tanks in the morning.

"I heard that we were going to have a big lunch rush because A and W had run out of propane," she said.

When the call to evacuate was made Wiseman said, "people were scrambling pretty quick in there."

Richard Birch, owner of Grower Direct, situated in the mall, said the timing of the evacuation was painful for business, but understandable.

"For this to happen during the lunch hour is pretty tough, but hey if it's a propane leak what can you do?" he said.