-呼吸停止：如果电流流过控制呼吸的肌肉
这些肌肉的不自主收缩改变了正常的呼吸
过程和受试者可能因窒息而死亡或遭受后果
窒息造成的创伤；
由于接触带电部件而导致人员受伤是由于
电流通过人体。影响包括：
-强直化：受电流影响的肌肉不自主收缩
松开被夹住的导电部件是困难的。注：非常高的电流
通常不要诱发肌肉强直，因为当身体接触时
这样的电流，肌肉收缩是如此持续，以至于
肌肉运动通常会使受试者远离传导
部分

-心室颤动：危险的影响是由于叠加
通过产生
不受控制的收缩会引起心动周期的改变。这种异常现象
可能成为不可逆转的现象，因为即使在
刺激已经停止；
-灼伤：它们是由于电流通过焦耳效应产生的热量引起的
穿过人体。
标准IEC 60479-1“电流对人和牲畜的影响”是
关于通过人体的电流影响的指南
电气安全要求的定义。本标准显示
时间-电流图，四个区域，交流对其的生理影响
与通过人体的电流（15÷100 Hz）有关。
4.1一般方面：电流对
人类
ABB |电气设备441
4保护人类
区
任命
AC-1
AC-2
AC-3
AC-4
AC-4.1
AC-4.2
AC-4.3
区
限制
高达0.5 mA
a线
0.5毫安
高达
b线*
b线
高达
曲线c1
在上面
曲线c1
c1-c2
c2-c3
超过
曲线c3
生理效应
通常没有反应。
通常没有有害的生理影响。
通常不会出现预期的有机损伤。电流持续时间内痉挛样肌肉收缩和呼吸困难的可能性
大于2秒。形成和传导的可逆干扰
心脏中的冲动，包括心房颤动和暂时性心脏病
无心室颤动的停搏随电流幅值增加而增加
还有时间。
随着幅度和时间的增加，危险的病理生理效应
例如心脏骤停、呼吸停止和严重烧伤可能发生在
除了3区的影响。
心室颤动的概率增加至约5%。
心室颤动的概率高达50%左右。
心室颤动的概率高于50%。
*对于低于10 ms的电流持续时间，线路b的体电流极限
在200 mA的值下保持恒定。
1SDC010042F0201
体电流IB
AC-1 AC-2 AC-3 AC-4
a b c1 c2 c3
10
5
太太
2
1
500
200
100
50
20
10
0,1 0,2 0,5 1 2 5 10 20 50 100 200 500 1.000 2.000 5.000 10.000
妈妈
电流持续时间t
AC-4.1
AC-4.2
AC-4.3
图1：交流电影响的时区
人类bod

to persons due to contact with live parts is caused by the flow of the current through the human body. The effects are: - tetanization: the muscles affected by the current flow involuntary contract and letting go of gripped conductive parts is difficult. Note: very high currents do not usually induce muscular tetanization because, when the body touches such currents, the muscular contraction is so sustained that the involuntary muscle movements generally throw the subject away from the conductive part; - breathing arrest: if the current flows through the muscles controlling the lungs, the involuntary contraction of these muscles alters the normal respiratory process and the subject may die due to suffocation or suffer the consequences of traumas caused by asphyxia; - ventricular fibrillation: the most dangerous effect is due to the superposition of the external currents with the physiological ones which, by generating uncontrolled contractions, induce alterations of the cardiac cycle. This anomaly may become an irreversible phenomenon since it persists even when the stimulus has ceased; - burns: they are due to the heating deriving, by Joule effect, from the current passing through the human body. The Standard IEC 60479-1 “Effects of current on human being and livestock” is a guide about the effects of current passing through the human body to be used for the definition of electrical safety requirements. This Standard shows, on a time-current diagram, four zones to which the physiological effects of alternating current (15 ÷100 Hz) passing through the human body have been related. 4.1 General aspects: effects of current on human beings ABB | Electrical devices 441 4 Protection of human beings Zone designation AC-1 AC-2 AC-3 AC-4 AC-4.1 AC-4.2 AC-4.3 Zone limits Up to 0.5 mA line a 0.5 mA up to line b* Line b up to curve c1 Above curve c1 c1 - c2 c2 - c3 Beyond curve c3 Physiological effects Usually no reaction. Usually no harmful physiological effects. Usually no organic damage to be expected. Likelihood of cramplike muscular contractions and difficulty in breathing for durations of current-flow longer than 2 s. Reversible disturbances of formation and conduction of impulses in the heart, including atrial fibrillation and transient cardiac arrest without ventricular fibrillation increasing with current magnitude and time. Increasing with magnitude and time, dangerous pathophysiological effects such as cardiac arrest, breathing arrest and severe burns may occur in addition to the effects of zone 3. Probability of ventricular fibrillation increasing up to about 5%. Probability of ventricular fibrillation up to about 50%. Probability of ventricular fibrillation above 50%. * For durations of current-flow below 10 ms, the limit for the body current for line b remains constant at a value of 200 mA. 1SDC010042F0201 Body current IB AC-1 AC-2 AC-3 AC-4 a b c1 c2 c3 10.000 5.000 ms 2.000 1.000 500 200 100 50 20 10 0,1 0,2 0,5 1 2 5 10 20 50 100 200 500 1.000 2.000 5.000 10.000 mA Duration of current flow t AC-4.1 AC-4.2 AC-4.3 Figure 1: Time-current zones of the effects of alternating current on the human bod