Sorry that I'm so late responding. Your new additon probably has 'backee stains on the floor already.
Assuming we're talking about a fairly standard board assembly area, you don't need to specify air quality.
1 We specify * Particulate: Level to be determined * Air Exchange: Controlled, monitored; complete air change minimum every three minutes with 5 to 20 percent make-up air added minimum air exchange (30 cubic feet per minute per person).
2 J-STD-001C specifies: Soldering area should be enclosed, temperature and humidity controlled, and maintained at positive pressure [or words to that effect]. It goes on to discuss the temperature and humidity limits further, but it sounds like you have those details well in hand.