The Harm Of Noise To Human Health

Occupational Noise Exposure Standards in China
According to China's occupational health regulations, workers are typically required to work 8 hours per day, 5 days per week. The occupational exposure limit for steady-state noise is set at 85 dB(A). For non-steady-state noise, the equivalent continuous sound level (Leq) is also capped at 85 dB(A).

Health Impacts of Noise
The effects of noise on human health are multifaceted, with the severity of harm increasing with higher noise intensity, frequency, duration of exposure, and reduced individual tolerance. The primary health consequences of noise exposure include:

Auditory System:
Prolonged exposure to high-intensity noise primarily leads to hearing impairment. Hearing loss progresses from temporary physiological effects to irreversible pathological damage, potentially resulting in deafness. Physiological hearing loss is reversible after a period of noise-free recovery, whereas pathological damage is permanent. Statistical data indicate:

Noise below 80 dB(A) does not typically cause noise-induced hearing loss, even with long-term exposure.

Noise between 80–85 dB(A) may cause minor hearing damage.

Noise between 85–100 dB(A) can lead to a significant incidence of noise-induced hearing loss.

Noise exceeding 100 dB(A) drastically increases the risk of hearing loss.

Sudden exposure to extremely high-intensity impulsive noise (e.g., explosions) can cause immediate and permanent hearing loss, known as explosive deafness, due to severe trauma to the auditory system.

Nervous System:
Chronic exposure to high noise levels can result in neurological disorders, including headaches, dizziness, tinnitus, palpitations, sleep disturbances, and memory impairment. It may also lead to emotional and behavioral changes, such as anxiety, irritability, nervousness, and mental fatigue.

Cardiovascular System:
Noise exposure can disrupt autonomic nervous system regulation, causing heart rate variability, unstable blood pressure (often elevated), and in severe cases, contribute to coronary heart disease and arteriosclerosis.

Digestive System:
Noise can induce gastrointestinal dysfunction, leading to symptoms such as loss of appetite, weight loss, reduced gastric acid secretion, and slowed gastrointestinal motility. These effects increase the risk of gastritis and gastric ulcers.

Reproductive and Menstrual Health:
Women exposed to noise may experience menstrual cycle irregularities, dysmenorrhea, and an increased incidence of spontaneous abortion. There is also a trend toward higher rates of pregnancy-induced hypertension syndrome.