What is the range of interest for the intensity component of sound?

• A. 0 - 140 dB
• B. -20 to 120 dB
• C. 10 - 150 dB
• D. 0 - 100 dB

Answer: (A)

The main idea here is understanding the practical span of sound intensity (in decibels) that is relevant for human exposure. Sound intensity level is measured on a decibel scale, and in most occupational hygiene contexts we think from the threshold of hearing at 0 dB up to the threshold of pain around 140 dB. This range covers everything from barely audible sounds to very loud noises that can cause immediate discomfort or damage, making it the most useful bounds for evaluating exposures and determining protective measures.

That’s why 0 to 140 dB is the best choice: it includes the quietest detectable sounds and extends to the upper limit before damage is likely, which aligns with how professionals assess and manage noise hazards. The other ranges either introduce values below the typical reference (negative values), push beyond commonly recognized pain levels, or omit the upper end still encountered in real environments, making them less appropriate for standard exposure considerations.