Can cause people to feel the minimum value of the current known as the perception of the current, AC 1mA, DC 5mA; people can get rid of their own current after electrocution is called the maximum current to get rid of the current, AC 10mA, DC 50mA; in a relatively short period of time endangering the life of the current known as the fatal current, such as 100mA current through the human body for 1s, it can be enough to make a person fatal in the case of electrocution protection devices to prevent the human body is allowed to pass through the current can be generally considered by the 30mA.

The human body's response to electrical currents.

8~10mA It is difficult to get rid of the electrodes, and there is a sharp pain (finger joints).

20~25mA Rapid paralysis of the hand, unable to get rid of the electrodes automatically, difficulty in breathing.

50~80mA Dyspnea, atrial fibrillation.

90~100mA respiratory paralysis, after three seconds the heart starts to paralyze and stops beating.

(1) Body resistance:

Human body resistance is mainly skin resistance, the epidermis 0.05 ~ 0.2mm thick stratum corneum resistance is very large, the skin dry, the human body resistance of about 6 ~ 10kΩ, or even as high as 100kΩ; but the stratum corneum is easily destroyed, remove the stratum corneum of the skin resistance of about 800 ~ 1200Ω; the resistance of the internal tissues of about 500 ~ 800Ω.

(2) Touch voltage:

The higher the voltage, the greater the danger automatic plug-in line, wool sweater factory, Tianjin rental car, bending machine, LED wall washer lamp shell, Tianjin discount air tickets, brand underwear. The human body will be in danger if it passes a current of more than 10mA. Therefore, to make the current through the human body is less than 10mA, if the human body resistance according to 1200Ω, according to Ohm's law: U = IR = 0.01 × 1200 = 12 V. If the voltage is less than 12 V, then the electrocution voltage is less than 12 V, the current is less than 10mA, the human body is safe. Our regulations: especially wet, easy to conduct electricity, 12V is a safe voltage. If the air is dry, better conditions, available 24V or 36V voltage. In general, 12V, 24V, 36V are three levels of safe voltage.

(3) Electrocution time: the longer the duration of the electrocution, the more serious the consequences. Electrocution current and time relationship is: the current of the milliampere multiplied by the duration, expressed in mA-s. Our country stipulates 50mA-s for the safety value. Beyond this value, it will cause harm to the human body.

(4) Electrocution parts and health conditions:  The degree of harm is greater when the electrocution current flows through the respiratory organs and nerve centers; the degree of harm is greater when it flows through the heart; and when it flows through the brain, it will cause people to fall unconscious immediately. Heart disease, endocrine disorders, lung disease, psychiatric patients, in the same situation, the degree of danger is greater.

So why is it that every household has installed a small circuit breaker (leakage action current is usually 30mA), and another leakage protection plug has to be installed on the electric water heater (or any other electrical appliance that has the potential for leakage)? Because the leakage protection plug for general household use has a leakage action current of 6mA or 10mA; it is more sensitive and safer than a small circuit breaker with a leakage action current of 30mA. It is more effective and safer especially for children and the elderly.