Does my utility room need fresh air? If so, possible solutions?
In the remodels I have done with open combustion inside a house we were required to have the 2 vents  I normally put 1 in the wall close to the ceiling and one in the wall at the floor with each being ~1 sq ft vented to the attic on single story.
 This is for fresh air not exhaust and I was told having the 2 zones helps to mix the air in the room and the exhaust goes out the vent on the water heater. I thought it sounded excessive but was easy to bring the vent’s in a non load bearing stud chase both were on the same one and by cutting out most of the walls top plate between these 2 studs on a non load bearing wall provided enough to pass inspection. This passed inspection the handful of times I did it, one being on my own home when I converted it to gas.  On 1 home I was required to install duct work in the stud bay and connect the vents , the vents must be fixed no dampers. The home that I was required to use ducting was a multi family dwelling and the wall I was using was common but not load bearing, the duct is easy to install remove the Sheetrock down 1 stud bay and purchase square duct put it in the bay replace the Sheetrock install the vents and it ends up looking like part of the heating system. If you can just use the stud bay cut the holes for the vent registers cut through the top plate I used a reciprocating saw so those were easy.