Audible Range

What Does Audible Range Mean?

The audible range is the set of sound frequencies that can be heard by humans. The human audible range is commonly listed as 20 to 20,000 Hz, although there are considerable variations between individuals, particularly at high frequencies. Gradual loss of sensitivity to higher frequencies with age is also typical.

Audible range is also known as the hearing range.

Safeopedia Explains Audible Range

Excessive noise is a common occupational hazard. According to estimates by the Center for Disease Control (CDC), each year about 22 million people are exposed to potentially damaging noise at work.

Exposure to noise can cause hearing damage, reducing an individual’s audible range.

Health Effects of Occupational Noise Exposure

Exposure to low- or high-frequency sounds can cause two types of adverse health effects.

Low frequency sounds (sounds well below the audible range) have non-auditory effects caused from changes in the way the inner ear works. Examples of such sounds include wind turbines and jet engines.

Sounds higher on the audible range, on the other hand, can cause auditory effects like hearing loss. Often, this is due to repeat exposure to excessive noise over time, although if it is loud enough a single exposure can be sufficient to cause hearing loss. This is the type of noise workers are exposed to from power tools and heavy machinery.

Nonauditory effects include:

• Physiological effects, such as a startle response to loud noise, changes in respiratory rhythms, change in heartbeat patterns, and change in the diameter of blood vessels.
• Difficulty understanding speech.

Auditory effects include:

• Acoustic trauma
• Tinnitus (a constant ringing or buzzing in the ear)
• Temporary hearing loss, known as a temporary threshold shift (TTS)
• Permanent hearing loss, a chronic condition that can worsen with continued exposure to loud noise

Safe Sound Levels

According to the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO), environmental noise should be maintained below 70 dBA over 24 hours. The EPA also recommends limits for speech interference for outdoor activities at 55 dBA and for indoor activities at 45 dBA.