The value of current flowing through the human body depends on the applied voltage and the resistance of the body. The higher the voltage the more current passes through a person.
The resistance of the human body is variable and depends on many factors - skin condition, size and density of contact, applied voltage, current exposure time.
The current flowing through the human body depends on the voltage electrical systems, strategies to incorporate human rights and capacity of an electric network to ground. Distinguish two-and single-pole electrical contact person is often under stress. Two-pole touch is simultaneously touching two electrical poles in tension. Single-pole touch is touching one pole. If the electrical installation is to install the AC, such contact is called, respectively, two-phase or single phase.
Two-phase bipolar or touch is the most dangerous, as in this case touch voltage and the maximum equal to the voltage network.
The analysis of injury shows that more than half of the electrical accident occurs when you touch the live parts of equipment. Electrical current-carrying part is that part of which is in operation an electric current. An example of live parts may be wires, contacts, equipment. To protect against access to frequently used fencing, locks, electrical insulation of live parts. Live parts are placed on height inaccessible or isolated by
cabinets, racks, screens. Fences shall be continuous and carried out so that they can only close and tools or other devices. Mesh fencing, doors, closed the castle used in high-risk and prevent the access of the most dangerous areas.
Isolation is not just for cable protection
from mechanical damage, but
and to protect people from exposure to electrical current. Sheath of rubber, plastics, cotton protects live parts from accidental contact.
In cases where live parts to protect or isolate impossible or impractical (eg, wires, cart, stifling power lines and communication lines), have to live parts inaccessible height. The wires of electric lines with a voltage up to 1000 Outdoor suspended at a height of not less than 6 m. In the production areas unprotected live parts have a height of not less than 3.5 m above the floor.
In order to warn people of impending danger of electric shock in a place where work or make it possible to find people who posted the warning signs - warning: "High Voltage! Danger to life, "" Stop! High Voltage ", prohibiting," Do not include - working people ", allowing" work here ", reminiscent of" grounded. " |