You may= have seen them working Tuesday.

Every on duty firefighter worked on this training program. It's all about ventilation. These square holes help release smoke during a fire.

The building is city owned and destined for demolition, but this type of building is perfect for learning.

Firefighters first approach the roof with hook ladders, but once several holes make the roof unstable they switch to using a ladder truck for safety.

"It's to simulate when you do have a fire and it's full of smoke when you ventilate the home then it allows you to see more clearly, gets the smoke out of the house, and in some cases, minimizes the damage," says Lt. Kevin Siers.

Lieutenant Siers says there is some type of training during every shift because you never know what the situation may be when the horn sounds.