How many volts does the dangerous voltage for an electric shock accident usually start?

Safe voltage refers to the voltage at which the human body does not cause any damage to the tissues (such as the heart, respiratory organs and nervous system) after the human body comes into contact with the charged body under various environmental conditions. On the one hand, the safety voltage is relative to the level of voltage, but it mainly refers to the voltage that poses little or no threat to human safety. The division of the safe voltage is related to the resistance of the human body and the allowable current of the human body.

The resistance of the human body is not a pure resistance, in addition to the resistance, it also contains a capacitive reactance in parallel with the ** resistance. Since the capacitance value is small, it is negligible. The internal resistance value of the human body mainly depends on the fat and thin degree of the human body, which is basically not affected by external factors, and its value is about 500, but the resistance is very different with different conditions, so that the resistance of the human body also varies in a large range.

There are many factors that affect the resistance of the human body, in addition to the thickness, moisture, sweating, damage, conductive dust, etc. will reduce the resistance of the human body. Increasing the contact area and increasing the contact pressure will also reduce the resistance of the human body. The increase in contact voltage will break through the stratum corneum of the epidermis and increase the body's body electrolysis, which will also reduce the body's electrical resistance.

In addition, the body resistance also decreases with the increase in the frequency of the power supply, for example, the body resistance at 100kHz is about half that at 50Hz. Under normal circumstances, the resistance of the human body can be considered as 1000 1500, and the lowest can be considered as 800. Through experiments and analysis, it is known that the power frequency limit current allowed by the human body is about 50mA, so it can be calculated according to Ohm's law, U=IR, and the maximum power frequency voltage allowed by the human body is about 40V.

Therefore, the safety voltage in China is stipulated to be 36V and 12V. For those places with poor working environment, that is, large pipes, mines, boilers and other metal containers with good electrical conductivity, lower human body resistance or increased contact opportunities, the safety voltage should also be set lower, usually 24V or 12V. For 12V, it is also called the absolute safe voltage.

The International Electrotechnical Commission (IEC) has limited values of 50V and 25V for contact voltage, which is based on the product of the allowable current and resistance of the human body. Among them, the 50V level is roughly equivalent to the case of the allowable current of the human body of 30mA and the resistance of the human body of 1600, that is, it is equivalent to the safety voltage of the general environment. 25V level, roughly equivalent to the human body allowable current of 30mA, human body resistance of 800, that is, equivalent to the safe voltage of the hazardous environment.

The safe voltage is 36V, and it depends on what type of electricity (AC or DC, how big the current is), which also varies from person to person, and some people have relatively large body resistance, and they can even connect more than 100V of electricity when they are electrified.

Don't try it lightly.

The voltage of an electric shock code accident generally starts from 65 volts, but a voltage of 36 volts can cause people to be electrocuted.

It is specified in the safety voltage in our country. When the equipment is more than 24 volts, it is necessary to take precautions to prevent direct contact with charged bodies.

Usually the electric shock is caused by the lack of knowledge of safe electricity use, not following the rules and regulations when carrying out electrical work, and there will be electric shock caused by accidents when it rains and lightning.

The dangerous voltage in the event of an electric shock accident generally starts at 36 volts.

Generally, if the voltage exceeds 36V, there will be a risk of electric shock. 36V is known as the safe voltage.

When the current flows through the human body, the damage to the physiological functions caused by the human body is called the personal electrocution aging accident. The severity of the injury to the human body by the electric current is generally related to the size, time, location, frequency and physical condition of the electric current passing through the human body. For adults, the weaning current is about 15 mA or less, and the weaning current is considered to be an electric current that the human body can only tolerate for a short period of time and generally does not cause danger.

The smallest current that can be life-threatening for a short period of time is called a lethal current. When the current passing through the human body reaches more than 50 mA, it is life-threatening.

The voltage is also known as the potential difference.

or potential difference, is a physical quantity that measures the energy difference between a unit charge in an electrostatic field due to different potentials. SI system of units for voltage.

For volts, the commonly used units are millivolts, microvolts, kilovolts, etc. Voltage is the reason why the free charges move in a direction to form an electric current in a circuit. The magnitude of the rock-bearing voltage from one point to another is equal to the work done by the unit positive charge to move from one point to another due to the action of the electric field force, and the direction of the voltage is specified as the direction from the high potential to the low potential.

65 volts. The voltage for an electric shock accident usually starts at 65 volts, but a voltage of 36 volts can be a risk of electric shock. It is stipulated in the safety of electric mold bending leakage voltage in our country.

When the electrical equipment is rotten for more than 24 volts, it is necessary to take protective measures to prevent direct contact with the charged body. The electric shock caused by the accident is due to the lack of knowledge of safe electricity use, the failure to follow the rules and regulations when working on electrical appliances, and the electric shock caused by accidents when it rains and lightning. ”

Voltages above 36 volts may cause electric shock, and the safe voltage is generally below 36 volts.

Dry places are generally above 36 volts, wet places will reduce the resistance of the human body, and the corresponding safety voltage will also drop to 24 volts or even 12 volts

It is specified that the safety voltage is below 36V. After 36v, there are dangers.

48 volts is the safe voltage, and electric shock is possible above 60 volts.

Human body safety voltage: not higher than 36 volts. Voltages above this can be dangerous.

The dangerous voltage of an electric shock accident is generally more than 65 volts.

An electric shock accident is a catastrophic accident with very serious consequences, and we must resolutely avoid and protect the injuries caused by electric shock. After all, there is only one life, and you need to cherish and protect it. Don't regret being careless.

The cause of electric shock, an electric current passing through the human body causes an electric shock. The occurrence of electric shock accidents is related to the magnitude, frequency, route and time of passage of electric current through the human body. Only voltages not higher than 36V are safe for the human body.

The higher the voltage, the stronger the current through the human body, and the more harmful it is.

In circuits that do not meet the requirements of current limiting circuits and do not meet the requirements of TNV circuits, the value voltage where the AC peak value exceeds or the DC value exceeds 60V is a dangerous voltage, and it is also the voltage that is most likely to cause harm.

Precautions in case of electric shock accidents. The action must be fast to minimize the electrification time of the electrocuted person. Do not directly touch the body of the electrocuted person or the wires in contact with the electrocuted person with your hands or metal and wet conductive objects, so as not to cause electric shock to the rescuers themselves.

When helping the electrocuted person to get off the power supply, care should be taken to prevent the electrocuted person from being injured by falling. Rescue breaths or chest compressions should not be easily interrupted.

Electric shock injury is one of the "five major injuries" in the common accidents in the construction industry, compared with other accidents, it is characterized by the fact that the omen of the accident is not intuitive and obvious, and the harm of the accident is very large. When the current flowing through the human body is less than 10mA, the human body does not produce dangerous pathophysiological effects.

However, when the current flowing through the human body is greater than 10mA, the human body will have dangerous pathophysiological effects, and with the increase of the current, the increase of time will produce ventricular fibrillation, and even human suffocation (suspended animation), which will take the life of a person in an instant or within two or three minutes. Therefore, in the case of incomplete protection facilities, human electric shock injuries are very likely to occur. Therefore, during the construction, we should do a good job of prevention, and when an electric shock accident occurs, it should be handled correctly to rescue the injured.

The dangerous voltage in the event of an electric shock accident generally starts at 65V.

In life, we should pay attention to the safety of electricity, and the general electric shock is caused by the lack of knowledge of safe electricity use, the installation and maintenance of electrical appliances, and the operation of wires not in accordance with the regulations. In addition, high temperature, high humidity and sweating reduce the surface resistance, which is easy to cause electrical damage. Electrical damage can be caused by electrical injuries caused by electrical wires broken and falling to the human body during an accident, sheltering from a tree during a thunderstorm, or being struck by lightning with an umbrella with an iron handle.

Safety voltage. When a person touches a live wire, the current will pass through the human body, which is called an electric shock. When an electric current passes through the human body, it can cause varying degrees of damage to the human body and internal tissues. There are two types of injuries: electric shock and electric injury.

Electric shock refers to the relatively serious damage to internal tissues caused by electric current passing through the human body.

If the electric current continues to pass through the human body, the heart, respiratory function and nervous system of the electrocuted person will be injured until they stop breathing, and the cardiac activity will stop as death. Electrical injury refers to the localized damage caused by an electric current to the outside of the human body.

Generally, if the voltage exceeds 36V, there is a risk of electric shock. 36v is called"Safety voltage. "。According to the Chinese national standard GB3805-83 "Safety Voltage", there are five levels of safety voltage value, and it is also specified:

When electrical equipment is used for more than 24V, protective measures must be taken to prevent contact with live bodies. For a specific power supply voltage series, the upper voltage limit between any two conductors or between conductors and ground shall not exceed 50V AC voltage under normal and fault conditions. Because although it is working at a safe voltage, although it will not cause death once electrocuted, if it is not removed in time, it will also have serious consequences after a long time.

In addition, the power supply voltage shall not be greater than 36V for lighting in tunnels, civil air defense projects, places with high temperature, conductive dust or lamps below the height of the ground, and the lighting power supply voltage shall not be greater than 24V in wet and easily accessible places with live bodies. In particularly humid places, the voltage of the lighting power supply working in a well-conductive ground, boiler or metal container shall not be greater than 12V. In case of electric shock.

China's voltage standard stipulates that within 36V is the safe voltage, and electric shock above 36V will harm the human body, the higher the voltage, the higher the risk, and the higher the mortality rate of electric shock accidents.

Generally speaking, the voltage of this voltage must be relatively large, so you must be careful when measuring.