The Hidden Health Risks of Noise and What You Can Do About It

01
Definition and Impact of Noise

❒ Definition and Classification of Noise
Noise is perceived as loud and discordant sound, measured in decibels, which disrupts daily rest, conversation, and work efficiency.

How does this annoying, uncomfortable, and unbearable noise affect the human body? Below, we will briefly explore this question.

❒ Noise Intensity and Impact
Noise, a common sound pollution we encounter in our daily lives, is measured in a specific international unit: the decibel, or dB.

Noise levels above 0 decibels negatively impact rest and sleep. This level of sound intensity is roughly equivalent to the sound of ordinary rain, a gentle breeze rustling leaves, or the chirping of birds. In these environments, people often struggle to get a good night's sleep.

Noise levels above 0 decibels disrupt conversations, hinder hearing, and thus affect work. This level of sound intensity is comparable to the background hum of busy city traffic, the crackling of heavy rain, and the whistling of strong winds. In such an environment, people struggle to communicate clearly and concentrate on their work.

Long-term exposure to noise levels above 85 decibels can cause hearing loss or even occupational deafness, while also disrupting the normal functioning of other human systems. This level of sound intensity is equivalent to the howling of a force 8 wind gust through the trees, the roar of a large waterfall heard up close, or even the deafening roar of a lion or tiger.

❒ Damage to Hearing
Noise damage to the auditory organs typically follows a progression from physiological changes to pathological changes. Initially, people experience a temporary shift in hearing thresholds, meaning that after being stimulated by noise, the ears require louder sounds to perceive. With continued noise exposure, this temporary shift can gradually develop into a permanent shift, resulting in substantial damage to the auditory system and long-term hearing loss.

02
Other Physical Effects and Symptoms of Noise

❒ Auditory Fatigue and Permanent Shift in Hearing Thresholds
Temporary shift in hearing thresholds refers to a change in hearing threshold levels after exposure to high-intensity noise. This change is reversible; once out of the noisy environment and after a period of rest, hearing typically returns to its original level. The degree of this shift can be categorized as auditory adaptation or auditory fatigue.

Auditory fatigue is a temporary protective mechanism, while a permanent shift in hearing thresholds can lead to deafness and severely impact quality of life.

❒ Damage to Auditory Cilia
Normal auditory cilia are crucial structures in the inner ear, responsible for capturing sound signals and converting them into neural signals for transmission to the brain for processing. However, chronic exposure to high-intensity noise can damage these cilia, leading to hearing loss or even a permanent shift in hearing thresholds.

Long-term exposure to high-intensity noise can damage auditory cilia, leading to hearing loss or even a permanent shift in hearing thresholds. The early manifestation of this damage is often a decrease in high-frequency hearing, primarily in the 3000Hz to 6000Hz range.

03
Differentiating Sounds of Different Frequencies

❒ Sound Frequency Range and Characteristics
High-frequency sounds generally refer to sounds in the 4000Hz to 20000Hz range. These sounds are characterized by shorter wavelengths, strong directionality, and a sharp, crisp sound.

Mid-frequency sounds, with frequencies roughly between 250Hz and 4000Hz, include everyday conversations, the melodious chirping of insects and birds, and the beautiful notes played in the middle register of a guitar.

Low-frequency sounds, with frequencies generally between 20Hz and 250Hz, encompass many familiar sounds in our daily lives, such as the rumbling sound of thunder and the roar of car engines.

04
Symptoms and Preventative Measures of Noise Harm

❒ Symptoms and Impacts on Body Systems
The harmful effects of noise on the human body are not limited to hearing loss; they can also cause a range of clinical symptoms. In addition to deafness and hearing loss, these symptoms include headaches, dizziness, memory loss, difficulty concentrating, and insomnia.

Symptoms such as tinnitus, earache, nausea, vomiting, and dizziness are all symptoms of noise exposure.

❒ Prevention and Treatment Measures
Currently, there is no definitive and effective treatment for noise-induced hearing loss. While there is no specific treatment, it can be effectively prevented by reducing exposure and wearing ear protectors.

Therefore, it is particularly important for people working in noisy environments to take hearing protection measures early. Wearing appropriately sized earplugs or earmuffs and strengthening preventive measures are key to protecting hearing and preventing noise-induced hearing loss.

Regular audiometry can ensure the effectiveness of protective measures.

When working in noisy environments, it is important to balance work and rest periods and avoid long periods of continuous work to prevent the accumulation of auditory fatigue.