Sound becomes hazardous noise pollution at level above

A. 30 dB

B. 120 dB

C. 80 dB

D. 150 dB

Sound levels are measured in decibels (dB). A sound level of 80 dB or above is considered noise pollution, which can lead to serious health issues such as hearing loss, stress, hypertension, and increased cholesterol levels. The safe average limit is around 50 dB.

Noise, or unwanted sound, has become an unavoidable part of modern urban and industrial life. Major sources include loudspeakers, factories, airplanes, trains, construction activities, and even radios.

Exposure to 80 dB or more for over 8 hours daily can increase stress, alter breathing patterns, and eventually cause fatigue, hearing impairment, or permanent hearing loss. Continuous noise above 120 dB may trigger harmful biochemical changes, including high blood pressure and increased white blood cell count.

At home, noise mainly affects sleep, concentration, and speech clarity. To prevent sleep disturbance, the indoor recommended limit is 30 dB (continuous noise) and 45 dB (single noise events). Prolonged exposure to 150 dB noise can be extremely painful and result in complete hearing damage.

Hence, the correct answer is: Option (C).