Indoor Air Quality and Ventilation Standards Flashcards

Under ASHRAE 62.1, what air class applies to commercial kitchen grease hood exhaust?

Answer: Class 4

Kitchen grease hood exhaust is Class 4, so it may not be recirculated or transferred.

In a multiple-zone recirculating system under ASHRAE 62.1, how is outdoor air intake flow (Vot) determined?

Answer: Vot = Vou / Ev

Uncorrected outdoor air Vou is divided by system ventilation efficiency Ev, which is less than 1, so the intake must increase.

What zone air distribution effectiveness (Ez) does ASHRAE 62.1 assign to low-velocity displacement ventilation (cool air supplied at the floor, ceiling return)?

Answer: 1.2

Displacement ventilation moves contaminants upward out of the breathing zone and earns Ez = 1.2.

Under ASHRAE 170, what are the minimum total and outdoor air change rates for an operating room?

Answer: 20 total ACH, 4 outdoor ACH

Standard 170 requires 20 total ACH and 4 outdoor ACH, with positive pressure, for operating rooms.

Per ASHRAE 170, an airborne infection isolation (AII) room must have which pressure relationship and minimum total air change rate?

Answer: Negative pressure, 12 ACH

AII rooms are held negative to adjacent spaces at a minimum of 12 total ACH to contain infectious aerosols.

For a naturally ventilated zone under ASHRAE 62.1, what minimum openable area is required as a percentage of net occupiable floor area?

Answer: 4%

62.1 requires openings of at least 4% of the net occupiable floor area of the ventilated space.

What is the main goal of demand-controlled ventilation (DCV) in buildings designed to ASHRAE 62.1?

Answer: Reset outdoor air intake based on actual occupancy

DCV lowers outdoor air when occupancy drops, often using CO2 or occupancy sensors, while still meeting 62.1 rates.