Effects on nervous system: neurasthenia syndrome groups such as headache, brain swelling, dizziness, tinnitus, dreaminess, insomnia, palpitation and memory loss. Effects on cardiovascular system: sympathetic nervous tension, rapid heartbeat, arrhythmia, ECG T wave changes, conduction block. Blood pressure changes. Effects on visual organs: eye pain, decreased vision. Effects on digestive system: loss of appetite, nausea and decreased gastric tension. Noise deafness Noise deafness refers to the deafness caused by the operator working in a strong noise environment. Noise deafness is not easy to be found early, because the hearing range of human ear is 20~20000HZ, but it is highly sensitive to high-frequency sound of 2000~8000HZ. The early loss is mainly in the high frequency range. The International Organization for Standards (ISO) defines hearing loss of 25 dB as the deafness standard. The normal hearing of human ears is 55 ~65dB, and some can be as low as 15 dB. It is generally believed that hearing loss of 25~40 decibels is mild deafness, 40~55 is moderate deafness, 70~90 is severe deafness, and over 90 is extremely severe deafness. Controlling and eliminating noise sources is the fundamental measure. Through technological reform, high-pitched equipment is replaced by mute or bass equipment and technology.