Which system has the best IAQ?

[ka24de]

I know all water 2 or 4 pipe fan coil system is NOT it.

1)Local vs. Central - as I see it both can have the same level of IAQ but books says Central offer better IAQ.......WHY?

2)Package and split - Which is better at IAQ or just the same?

[syntropicsystems]

Look at the needs of the facility. If you're pulling in outside air, you'll need filtration according to the levels of outside pollution. I recommend using or installing a proprietary photocatalytic oxidation (PCO) system called DuctwoRx if you're trying to reduce microbials and VOCs throughout the facility. You might need to combine it with something else, depending upon what you're dealing with inside. There are no perfect solutions that work every time. You need to fit the equipment to the facility. Unfortunately the facility cannot always afford the right equipment.