What are the basic measures for lightning protection?

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file:///E:/DOCUME~1/zzjjaa/LOCALS~1/Temp/ksohtml/wps_clip_image1.png What are the basic measures for lightning protection? (1) Lightning protection devices take advantage of their elevated position above the protected objects to draw lightning to themselves, and then channel the lightning current into the ground through down conductors and grounding systems. Common lightning protection devices include: lightning rods, lightning nets, lightning strips, lightning conductors, and surge protectors. Depending on the object to be protected, lightning arresters can be lightning rods, lightning conductors, lightning grids, or lightning strips. Lightning rods are primarily used for the protection of buildings and structures ； Lightning conductors are primarily used as protection for power lines ； Lightning protection nets and belts are primarily used for the protection of buildings ； A lightning arrester is a protective device that prevents lightning intrusion waves. (2) Ionization lightning protection is a new technology that consists of an ionization device at the top, a ground current collection device underground, and connecting wires. Ionization lightning protection devices utilize the induction effect of thunderclouds, or employ radioactive elements to create a strong electric field near the ionization device, thereby ionizing the air and generating an ion flow that moves toward the thunderclouds. In this way, the charge carried by the thunderclouds can be slowly neutralized and dissipated, so that the electric field strength in the air does not exceed the breakdown strength of air; this eliminates the conditions necessary for lightning strikes and prevents them from occurring. (3) The lightning protection measures for storage tanks of flammable and combustible liquids are as follows: 1) Lightning protection for metal oil tanks: Since metal oil tanks have good shielding properties, as long as the roof of the tank has sufficient thickness, their inherent protective capabilities are sufficient to meet the requirements. When the thickness of the oil tank roof is greater than 3.5 millimeters (mm) and it is equipped with a vent valve, a lightning protection device is not required. However, the oil tank body must be properly grounded, with no fewer than two grounding points, spaced no more than 30 meters apart. When the thickness of the tank top plate is less than 3.5 millimeters, even if a vent valve is installed, a lightning rod must also be installed on the tank top, and the horizontal distance between the lightning rod and the vent valve should not be less than 3 meters. The protection range above the breather valve should be no less than 2 meters (m). 2) For the lightning protection of non-metallic oil tanks, separate lightning rods should be used to prevent direct lightning strikes. At the same time, measures to prevent lightning induction should also be in place. For underground non-metallic oil tanks with a soil cover thickness greater than 0.5 meters, lightning protection measures need not be considered. However, the breather valve, oil measurement hole, and lighting hole should be properly grounded, with no fewer than two grounding points.