Human Hearing Range: Frequency (Hz) and Volume (dB)

Article by Hearing Partners, contributed by Nur Sadrina, Senior Clinical Audiologist at Hearing Partners

Human ears are remarkably sensitive, capable of detecting everything from soft whispers to loud explosions. The ability to perceive sounds across this spectrum hinges on two fundamental elements: frequency and loudness.

Frequency, measured in hertz (Hz), determines whether a sound is perceived as high-pitched or low-pitched. On the other hand, loudness, measured in decibels (dB), dictates how soft or loud a sound appears to us.

Read on for the difference in hearing range between those with and without hearing loss, and learn how hearing loss is diagnosed.

Normal Human Hearing Range

The normal human hearing range can be defined using frequency and loudness.

Frequency or pitch

The typical range of frequencies humans can hear spans from 20 Hz to 20,000 Hz (20 kHz). This spectrum stretches from deep bass tones to high-pitched sounds. For most individuals, the highest-pitched sounds they can perceive fall within the range of 15 kHz to 17 kHz.

Speech consists of a wide range of frequencies that contribute to its clarity and intelligibility. Most vowel sounds lie in the range of 250 to 2000 Hz, while consonant sounds (f, s, th, etc.) lie in the higher frequency range of 2000 to 8000 Hz. Therefore, to be able to understand speech clearly, it is important to have good hearing across the entire range of frequencies of 250 to 8000 Hz.

Volume or loudness

The range of sound intensities (loudness levels) that a human can perceive is referred to as the dynamic range. It ranges from the faintest sound that can be detected by humans to the loudest sound that can be tolerated without being uncomfortably loud.

A typical dynamic range of human hearing spans from 0 to 130 decibels (dBA). Various everyday sounds fall within this spectrum, and while some are safe for the ears, others are dangerously loud.

Noise-Levels-of-Common-Sounds

Image credit: Hearing Partners

Generally, sounds at or below 70 dBA are safe for prolonged exposure. Examples of sounds within this range include:

Quiet sounds like the rustling of leaves: 20 dBA
Gentle rainfall: 40 dBA
Normal conversation between people: 60 dBA
Household vacuum cleaner: 70 dBA

Sounds become potentially harmful starting at 85 dBA and exposure must be limited to prevent hearing damage. For a sound level of 85 dBA, exposure for up to 8 hours a day is generally considered safe. However, a sound of 88 dBA is only safe for listening for a maximum of 4 hours and listening to a 91 dBA noise should be limited to 2 hours.

This is due to the fact that dB is a logarithmic unit, and an increase of 3 dB represents a doubling of sound intensity. Thus, for every 3 dB increase in volume, the maximum permissible exposure time is reduced by half before potential hearing damage occurs.

Hearing damage occurring due to loud sounds are known as noise-induced hearing loss. In Singapore, the Ministry of Manpower’s Workplace Safety and Health Report 2022 revealed that cases of noise-induced deafness increased significantly from 168 cases in 2021 to 624 cases in 2022.

Other examples of sounds louder than 85 dBA and are considered unsafe for prolonged exposure include:

Listening through earphones at maximum volume: 100 dBA
Ambulance siren: 120 dBA
Fireworks: 150 dBA

Hearing Range for Those With Hearing Loss

Hearing-Range-for-Those-With-Hearing-Loss

As people age, they often experience increased difficulty in perceiving higher-pitched sounds. Examples of high-pitched sounds are the chirping of birds or patter of raindrops. High-frequency sounds are processed in the base of the cochlea (hearing organ), which is more susceptible to wear and tear. Consequently, high-frequency hearing loss, or hearing loss from 2000 Hz onwards, is the most common type of hearing loss among elderly individuals.

In terms of loudness, those experiencing hearing loss will find their hearing threshold shifting upwards. This means that their hearing sensitivity decreases and detecting soft sounds becomes harder. Sounds need to be louder before they become audible.

The degree of severity of hearing loss is categorised into mild, moderate, severe or profound.

Degree of hearing loss	Characteristics and signs
Mild (21 – 40 dB HL)	Speech may be unclear in noisy environments Turning up the TV higher than normal
Moderate (41 – 55 dB HL)	Communication may be challenging without a hearing aid
Moderately severe (56 – 70 dB HL)	Communication may be challenging without a hearing aid Hearing speech clearly may still be challenging in noisy environments
Severe (71 – 90 dB HL)	Speech may be inaudible without hearing aids Environmental sounds are hard to hear Strategies to aid communication are needed, including: Lip-reading Sitting close to the speaker Requesting for the speaker to speak slowly and clearly
Profound (>91 dB HL)	Listening is difficult even with a hearing aid Strategies similar to those used by individuals with severe hearing loss are necessary for communication

Diagnosing Hearing Loss

If you’ve observed changes in your hearing as indicated by the signs mentioned above, you may wish to undergo a hearing test to determine your current hearing ability.

Through a series of assessments, the hearing care professional will assess your hearing across different frequencies and decibel levels. Based on the test results, they’ll identify if you suffer from hearing loss and suggest suitable treatments to improve your ability to hear and understand speech more effectively.

Protect Your Hearing

Early intervention plays a crucial role in managing hearing loss and mitigating its impact on your daily life. Through regular hearing tests, you can monitor changes in your hearing and take the necessary steps promptly to prevent deterioration. Take charge of your hearing health today by scheduling a hearing test at your nearest clinic.