I'm a fan of DK books.
They're simple. They're informative. They're cheap. If your child is too young to read, they're perfectly good read-aloud books.
What more can you ask for when stocking your kid's library?
This is about a fire rescue. It's a little frightening for younger readers - after all, there's a fire and a kid possibly trapped inside - but nobody gets hurt so the fear turns into excitement.
I do wish, though, that the DK publishers would stop putting "fact boxes" on their pages. If the information cannot be integrated into the main story, it should be saved for a special page at the end. It's too distracting for early readers to be pulled out of the main text to read a little box on the side.