Question

at what decibel level is sound exposure considered potentially damaging to human hearing over an eight - hour period?
city traffic, 85 db
landscaping equipment at a distance, 75 db
electric vacuum, 80 db
background music, 60 db

Explanation:

According to the National Institute for Occupational Safety and Health (NIOSH), exposure to sounds at or above 85 dB for 8 hours or more can cause hearing loss. City traffic is typically around 85 dB, which meets this criterion. Landscaping equipment at a distance (75 dB) is below the 85 dB threshold. An electric vacuum (80 dB) is also below 85 dB. Background music (60 dB) is much lower than 85 dB.

Answer:

City Traffic, 85 dB