Fire separation and combustion air

I found this configuration odd and I’m not sure what to make of it. This home has a gas furnace and water heater located in a utility closet accessible from the garage. In this closet there are meta-caulk type ring seals around the plastic flue and vent pipes for the high-efficiency furnace. There was a metal fire stop around the water heater flue pipe.

The bad part, I think, is the upper and lower combustion air vents leading to the attic. As this closet is not protected by a fire rated door having the open C-Air vents defeats the purpose of the other fire separation means.

Is there a code reference for this? What do you all have to say? I’m just mulling over how I’m going to write this up - I’m considering just requiring a fire rated self closing door for this room.

Isn’t the fire rating required between the Garage and the house only?

The closet is in the House…But the door needs to be fire rated and sealed.