An electrical installation is the collective name of all electrical devices along with the structures in which they are located. They serve for the production of electric energy, its transmission and distribution, transformation into other types of energy.
An electrical installation is considered effective when it is energized or current appears after the switches are turned on, if there is a power line located nearby or intersecting with it. Electrical installations have direct or alternating current, the voltage sometimes exceeds 1000 volts.
The safety signs used in such installations are a color and graphic image of a certain form, on which inscriptions are made to warn workers about the danger, carrying some useful information on safety measures for people.
The need to warn workers
Safety posters in electrical installations are needed to ensure the safety of personnel working at the enterprise. They warn people in advance of the dangers of working with electric currents, in order to avoid injuries and deaths in the workplace. Saving human life is always a priority for any production manager, especially when it comes to electrical installations.
Posters and safety signs in electrical installations are used to prohibit or permit certain actions to be taken when the voltage is on, to notify employees about connected devices, about the distance that you can approach the switch to indicate the direction and location of structures and assemblies.
Types of hazard markings
There are several types of safety posters in electrical installations:
- The prohibition signs indicate that it is impossible to carry out any action or turn on the electricity when work is being carried out, and not to move around the territory without special protective equipment, in order to prevent an error when applying current to the workplace.
- Warning posters indicate the danger of finding or approaching live parts, connected wires, and devices under high voltage.
- Prescriptive plates give permission to perform an operation using a given place or apparatus, to approach elements that are already de-energized, and recommend that you fulfill some requirements.
- Pointing posters show employees the placement of various devices in the production, the direction of movement to objects of interest.
The difference between posters and signs by the nature of their use
Safety posters in electrical installations can be of two types. Permanent, which are in the same places, and portable, changing the location of production needs, based on work assignments and intentions. Safety signs are only permanent.
The material from which these products are made is also different. The use of only non-conductive products is recommended. These are such electrical insulating special materials as fiberglass, polystyrene, PVC, textolite, getinaks. If the signs are made of metal, then they can only be installed far from live parts or materials.
Signal colors
Posters and safety signs used in electrical installations have different signal colors. They are of the same type with all safety signs at production facilities in all countries of the world.
Prohibition signs are red; white has been added to it for the purpose of contrast. Such bright colors are taken for a better perception of visual information by people in the enterprise. Red color against a gray wall is clearly visible from afar. For example, the sign “DO NOT TURN ON! PEOPLE WORK! ” prohibits applying voltage to the line where the repair team is currently located, so as not to expose them to danger of electric shock.
Yellow is given to warning signs informing of imminent or probable danger. The contrasting color is the black bezel.
Blue and white are the colors of the prescriptive signs, introducing useful information regarding safety when working in electrical installations, denotes elements of technical information.
Green signs allow you to perform safe actions, show the way out, the direction of movement to the first-aid posts, the location of first-aid kits and warning lights.
Where do they use signs and posters?
Posters and safety signs used in electrical installations are installed in places of greatest danger to employees or on devices that pose a threat to human life. Thanks to the contrasting signal colors, they clearly stand out from the surrounding objects and equipment. They should be clearly visible to employees, but should not distract their attention. Also, the signs themselves can not be dangerous to others.
It is recommended that safety posters in electrical installations be installed above the enclosure area of hazardous equipment or live transmission lines. Prohibited signs are placed at a height of 0.5 m above the entrance to the structure or the top element of the fence. The distance is measured to the bottom of the sign.
Signs are also posted on the drives of disconnectors, circuit breakers, switching equipment, on the keys and buttons of the remote control, in machines, above the circuit breakers. Portable signs are hung out with a rope.
In settlements, signs that are mounted on poles of overhead power lines are located at a height of 2.5-3 meters from ground level. If the spans of the supports are frequent, less than 100 meters, then signs are posted through one support, if the spans are large, then on each. They also do this if the overpasses cross the power line.
The quality of paints and varnishes
It is recommended to apply posters and safety signs with paints using stencils on concrete or metal surfaces of equipment, supports of overhead transmission lines, doors of switch rooms or cameras. There are still convenient to use products on self-adhesive film.
Paints and varnishes should be signal colors and be resistant to changes in the climate and to various production conditions in the premises of which such graphic images are used. Over time, such safety features should not change color, should be clearly visible to the eye both in daylight and in the dark. At night and in conditions of poor visibility, it is recommended to illuminate posters and safety signs with additional lamps.
Self-adhesive signs
Materials used for the manufacture of safety posters in electrical installations must not conduct electrical current. The basis for such products is mainly PVC or polystyrene 3 mm. Several types of self-adhesive film are applied to these materials. This is a regular, reflective or light-accumulating series of products.
Sometimes a protective lamination of signs is applied on top. Such products are fastened with adhesive tape or hardware.
Standard character sizes
According to standard requirements of the instruction, the sizes of images depend on the types of safety posters in electrical installations. They can be large - 240x130 mm - or small - 80x50 mm.
Prohibition signs, such as “TEST. DANGEROUS FOR LIFE "or" DON'T CARE. KILL ", created in the size of 280x210 mm.
Warning signs of yellow color, according to the standard, the sizes of the sides are different, depending on their location on the territory of electrical installations. If the sign is placed on the building, then the side of the triangle is 360 mm. On the doors of the working premises - 160 mm, 100 mm or 80 mm. To place signs on small parts of equipment or containers, sizes are also reduced: 50 mm, 40 mm or 25 mm.
The use of posters and safety signs in electrical installations is of paramount importance to guarantee the preservation of human lives in the workplace. The head of the hazardous enterprise must constantly monitor compliance with all safety standards and rules, conduct familiarization and training classes for all employees, monitor the work process daily and bear personal responsibility for the safety of employees.