Which statement best describes the scope of ASHRAE Standard 62.1-2022 regarding residential spaces?

• A. It explicitly excludes spaces within dwelling units in residential occupancies.
• B. It applies to all spaces within dwelling units in residential occupancies.
• C. It excludes all spaces in non-residential buildings.
• D. It excludes some spaces in residential occupancies.

Answer: (A)

The main idea is understanding where ASHRAE 62.1-2022 applies when you have residential buildings. The standard is written to regulate ventilation and indoor air quality for nonresidential spaces, and it explicitly does not cover the interiors of individual dwelling units. So, while common areas or other non-dwelling spaces inside a residential building might fall under 62.1, the spaces inside each dwelling unit are outside its scope. For those residential interiors, another standard (ASHRAE 62.2) handles the requirements.

This is why the best description is that the scope explicitly excludes spaces within dwelling units in residential occupancies. The other statements don’t fit because 62.1 does not apply to all spaces within dwelling units, it does not exclude all non-residential building spaces, and it isn’t simply “excludes some spaces” in a broad sense—the exclusion is specifically about dwelling-unit interiors, with other non-dwelling spaces potentially covered.