“We heard a loud explosion and we felt the vibration of it. So, I ran outside ... to the buildings near the café,” Ouellette told Mike Finnerty on CBC’s Daybreak Montreal.
More than 100 firefighters were called to the scene, but the first to arrive wasn’t even on duty.
Ouellette was the only responder when he arrived at the propane tank explosion in a 52-unit apartment building on Belanger Street, between Garnier and Fabre.
“I saw a lot of windows blown away and smoke starting to come from inside the building,” said Ouellette, an acting lieutenant.
First, he went inside the building and told everyone to leave the first floor.
Then he headed up the staircase where he knocked on doors, yelling for people to get out of the building.
He found one man on crutches and helped him out of the building.
"The person was not able to get out by himself, so I helped," said Ouellette.
Then, as the smoke got thicker, he found the rest of the people on the second floor and led them downstairs by their hands.
“I had to back up because the smoke was very hot and the fire was raging there,” said Ouellette.
Unable to get to the upper floors, he left the building.
“People on the third floor and the fourth floor wanted to get out because there was smoke behind them, and they wanted to jump,” said Ouellette. “I was telling them not to jump.”
Ouellette then borrowed a ladder from a painting crew working nearby and climbed up to the windows before the on-duty firefighters arrived at the scene.
He said he also knew there could be delays, as some streets were closed because of the Montreal Marathon.
"I was not scared because I have the experience in those situations. It’s a part of my job," said Ouellette. "Sometimes when you’re facing a danger like that you evaluate the risk … I just did my best."
A 63-year-old man was taken to hospital and is still in critical condition with burns on close to 80 per cent of his body.
Another person is being treated for burns and is in serious condition. But Ouellette said it could have been much worse.
“I knew that the people there needed to get out fast,” said Ouellette. “I know for sure that six people were in big danger and needed help from someone.”
Paramedics also treated four people at the scene for smoke inhalation, including a firefighter.