CBD Ventilation & Mechanical Systems

Question 1

According to ASHRAE 62.2, what is the minimum recommended intermittent exhaust rate for a residential bathroom?

Accepted Answer

50 CFM

Answer

ASHRAE 62.2 specifies a minimum of 50 CFM for intermittent bathroom exhaust ventilation to adequately remove moisture and odors.

Question 2

Which organization certifies and rates residential exhaust fans for airflow performance and sound levels?

Accepted Answer

HVI (Home Ventilating Institute)

Answer

The Home Ventilating Institute (HVI) is the industry body that certifies exhaust fans for both airflow (CFM) and sound (sone) performance.

Question 3

A bathroom exhaust fan rated at 1.0 sone is best described as:

Accepted Answer

Very quiet, comparable to a library

Answer

A 1.0 sone rating is very quiet—equivalent to a quiet library—making it ideal for high-end bathroom installations where noise is a concern.

Question 4

What is the maximum recommended length of flexible exhaust duct allowed when connecting a bathroom exhaust fan to rigid ductwork?

Accepted Answer

6 feet

Answer

Most codes and manufacturer guidelines limit flexible duct connectors to 6 feet to minimize airflow restriction and moisture accumulation.

Question 5

Which exhaust fan control provides the most effective moisture management in a bathroom by responding directly to humidity levels?

Accepted Answer

Humidity-sensing switch

Answer

A humidity-sensing switch automatically activates the fan when relative humidity rises above a set point, directly addressing the source of moisture buildup.

(CBD) Certified Bathroom Designer Practice Test

(CBD) Certified Bathroom Designer Practice Test

CBD Ventilation & Mechanical Systems