HVAC Indoor Air Quality and Filtration 5

Question 1

When performing an IAQ investigation, which instrument measures airborne particulate matter concentration?

Accepted Answer

Particle counter

Answer

A particle counter measures the number and size distribution of airborne particles per cubic foot or cubic meter of sampled air.

Question 2

What is the term for the condition where chemical contaminants from one area migrate into another area through HVAC ductwork or building pressurization?

Accepted Answer

Cross-contamination

Answer

Cross-contamination occurs when airborne pollutants from one zone — such as a copy room or lab — migrate through shared HVAC systems into occupied spaces.

Question 3

Which ASHRAE standard covers residential ventilation requirements, including whole-house mechanical ventilation?

Accepted Answer

ASHRAE 62.2

Answer

ASHRAE 62.2 specifically addresses ventilation and IAQ requirements for low-rise residential buildings, including whole-building and local exhaust strategies.

Question 4

A technician finds microbial growth on cooling coil surfaces. Besides cleaning the coil, what HVAC design factor should be corrected to prevent recurrence?

Accepted Answer

Ensure the drain pan slopes properly and condensate drains freely

Answer

Standing water in improperly draining condensate pans provides the moisture environment that sustains biological growth on cooling coils.

Question 5

What does the term 'dilution ventilation' mean in IAQ practice?

Accepted Answer

Introducing outdoor air to reduce indoor contaminant concentrations

Answer

Dilution ventilation reduces indoor pollutant concentrations by mixing clean outdoor air with contaminated indoor air until acceptable levels are achieved.

HVAC Practice Test

HVAC Practice Test

HVAC Indoor Air Quality and Filtration 5