The Firefighters by Sue Whiting, illustrated by Donna Rawlins

From chapters.ca:
Children will want to grab their coats and boots and rush straight to this winsome firefighting tale full of sound words and bright illustrations. "Weee-ooo Weee-ooo Weee-ooo Our fire engines are fast and noisy - just like the real ones." From sounding the siren to speeding off in their fire engines (empty boxes will do), from finding the fire to expertly putting it out, the children love playing firefighters with Mrs. Iverson. They are brave and strong, just like real firefighters. And after a hard day of fighting fires, nothing is better than having two real live firefighters come to visit and getting to climb aboard their big, red, shiny fire engine