Machinery spaces must be designed to minimize the exposure of personnel to noise in accordance with U.S. regulations. Manned machinery space noise must not exceed which noise level?

Correct Answer: Option C — 90 dB(A)

46 CFR 197.500 establishes that noise levels in manned machinery spaces must not exceed 90 dB(A) to protect crew health and safety. This limit is a critical regulatory threshold for occupational exposure, requiring engineering controls or personal protective equipment if the ambient noise levels exceed this specified decibel limit.