An example of work exempt from permit requirements is ____.

An example of work exempt from permit requirements is ____.

• A. a humidifier added to a plenum
• B. moisture exhaust duct venting on a residential clothes dryer
• C. a branch duct added to at trunk line
• D. replacement of a minor part that does not alter the equipment

Answer: (D)

Work exempt from permit requirements covers tasks that don’t change how the system operates or affect safety features. Replacing a minor part that does not alter the equipment fits this because you’re restoring the unit without changing capacity, airflow, electrical load, or venting—there’s no new function to inspect. In contrast, adding a humidifier introduces a new device that affects humidity control and electrical/water connections; venting a clothes dryer adds ductwork with fire and moisture implications; and adding a branch duct changes airflow and system balance. All of these involve modifications to the system and would normally require a permit.

Work exempt from permit requirements covers tasks that don’t change how the system operates or affect safety features. Replacing a minor part that does not alter the equipment fits this because you’re restoring the unit without changing capacity, airflow, electrical load, or venting—there’s no new function to inspect. In contrast, adding a humidifier introduces a new device that affects humidity control and electrical/water connections; venting a clothes dryer adds ductwork with fire and moisture implications; and adding a branch duct changes airflow and system balance. All of these involve modifications to the system and would normally require a permit.