How is the concept of target IAQ described in ASHRAE 62.1?

• A. The IAQ goal achieved using IAQP or design strategy, not just minimum.
• B. Outdoor air quality equals target IAQ.
• C. Target IAQ is determined by occupant surveys.
• D. Target IAQ is the same as maximum allowed contaminant levels.

Answer: (B)

In ASHRAE 62.1, the target indoor air quality (IAQ) is described as the IAQ goal you would expect to have inside the space if the outdoor air used for ventilation were at the specified target outdoor air quality. In other words, the indoor goal is tied to the quality of the outdoor air; once you bring in that outdoor air (and treat it as needed with filtration and control), the indoors should reflect that target level. This makes the outdoor environment the reference point for what we’re aiming to achieve indoors, rather than basing the target on internal-only thresholds. The other ideas don’t define what target IAQ is: occupant surveys relate to perceived IAQ rather than the objective target; maximum allowed contaminant levels are regulatory limits and not the design target; and while IAQP or other design strategies are methods to meet the target, they describe how you achieve the target rather than what the target itself is.