Answer :
Final answer:
ASHRAE is the organization responsible for determining sound levels for mechanical systems in buildings, not OSHA which focuses on occupational noise exposure and PELs.
Explanation:
The standards organization that determines sound levels for mechanical systems in buildings is ASHRAE (the American Society of Heating, Refrigerating and Air-Conditioning Engineers). While OSHA (Occupational Safety and Health Administration) does develop legal standards for workplace exposure, such as Permissible Exposure Limits (PELs), these tend to focus on occupational noise as it pertains to workers' hearing conservation and noise exposure. ASHRAE, on the other hand, sets forth guidelines that affect building design and construction, including the sound levels of mechanical systems to ensure comfort and safety for occupants.