Final answer:
The average ambient sound pressure level (SPL) is measured over a 24-hour period. This allows for a comprehensive assessment of varying noise levels that occur during a full day cycle.
Step-by-step explanation:
The average ambient sound pressure level (SPL) is typically measured over a 24-hour period. This duration is standard to get a representative average of the varying levels of noise that can occur throughout a typical day, which can be affected by factors like traffic patterns, industrial activities, and human behaviors.
Sound pressure level is expressed in decibels (dB) and is used to describe the intensity of sound in the air. When sound travels in water, different decibel levels may be encountered, but for air, typical ambient measurements are taken over 24 hours. It's important to understand that exposure to sound levels above 85 dB for prolonged periods can be hazardous without proper hearing protection.