Slight, irreversible hearing loss may result for many people, from daily exposure over an 8 hour period of time to sound averaging:

Slight, irreversible hearing loss can occur from prolonged exposure to sound levels above a certain threshold, and studies indicate that 85 dB is a significant level of concern. At this decibel level, continuous exposure for an 8-hour workday is associated with an increased risk of developing hearing damage over time. The Occupational Safety and Health Administration (OSHA) establishes guidelines indicating that exposure to noise levels at or above 85 dB can lead to hearing loss.

When sound levels exceed this threshold, the hair cells in the inner ear can become damaged. Since these hair cells do not regenerate, this can result in permanent hearing loss. Regular monitoring and protective measures become essential in environments where noise levels reach or exceed this recommended limit. Therefore, identifying and controlling noise in the workplace is vital for protecting auditory health, particularly at 85 dB and above, which is why it is the correct answer for this question regarding irreversible hearing loss from daily exposure over an 8-hour period.