During the construction of security systems, people often hear the term "electrical protection level". So, what exactly is meant by "electrical protection level"? Today, I will explain it to you:

The first category of lightning protection buildings:

1 . Any building that manufactures, uses or stores large quantities of explosive substances such as explosives, gunpowder, initiating explosives, etc., and where an explosion occurs due to an electric spark, will cause tremendous damage and casualties.

2. Buildings with explosion-hazardous environments in Zone 0 or Zone 10.

3. Buildings with an explosive hazard environment in Zone 1, if an explosion occurs due to an electric spark, will cause severe damage and casualties.

The second type of lightning protection buildings:

1. A building that is a national-level key cultural relic protection site.

2. National-level buildings such as auditoriums, office buildings, large exhibition and exposition buildings, large railway stations, state guesthouses, national archives, and important water supply pump rooms in major cities, which are particularly significant buildings.

3. National-level computing centers, international communication hubs, etc., are buildings that are of great significance to the national economy and are equipped with a large number of electronic devices.

4. Buildings that manufacture, use or store explosive substances, and where an electric spark is unlikely to cause an explosion or result in significant damage and casualties.

5. Buildings with an explosive hazard environment in Zone 1, where electric sparks are unlikely to cause an explosion or do not result in significant damage or casualties to people.

6. Buildings with explosion-hazardous environments in Zone 2 or Zone 11.

7. There are open-air steel enclosed gas tanks with explosion hazards in industrial enterprises.

8. Buildings of provincial or ministerial level that are used for official purposes and other important or densely populated public buildings where the expected number of lightning strikes is greater than 0.06 times per year.

9. Residential buildings, office buildings and other general civil structures where the expected number of lightning strikes is greater than 0.3 times per year.

The third type of lightning protection buildings:

1. The provincial-level key-preserved buildings and the provincial-level archives.

2. Buildings of provincial and ministerial level offices, as well as important or densely populated public buildings, where the expected number of lightning strikes is greater than or equal to 0.012 times per year and less than or equal to 0.06 times per year.

3. Residential buildings, office buildings and other general civil structures where the expected number of lightning strikes is greater than or equal to 0.06 times per year and less than or equal to 0.3 times per year.

4. General industrial buildings where the expected number of lightning strikes is greater than or equal to 0.06 times per year.

5. Based on the impact and consequences of lightning strikes on industrial production, and taking into account local meteorological, topographical, geological and surrounding environmental factors, the fire hazard environments of zones 21, 22 and 23 that require lightning protection were determined.

6. In areas where the average number of thunderstorm days per year is greater than 15 days, isolated tall buildings such as chimneys and water towers with a height of 15 meters or more; in areas where the average number of thunderstorm days per year is less than or equal to 15 days, isolated tall buildings such as chimneys and water towers with a height of 20 meters or more.

The lightning protection design requirements for buildings:

The lightning protection design requirements for first-class lightning protection buildings

1. A lightning rod should be installed on the roof, or lightning protection strips should be set up at the corners, ridges, parapets and eaves of the building, and a metal grid no larger than 10m×10m should be installed on the roof.

2. First, the main reinforcement bars should be used as the down conductors. The column reinforcement bars at each exterior corner of the building should be utilized. If a separate down conductor is to be set up, it should be no less than 2. The spacing of the down conductors should not exceed 18 meters.

3. The electrical lines and metal pipes entering the building should be introduced by underground laying throughout the entire length, and at the entrance, the metal sheath of the cables, steel pipes, and metal pipelines should be connected to the grounding device.

4. The impulse grounding resistance of the grounding device should not exceed 10 ohms.

5. For every three floors, the steel bars of the concrete ring beams or flat steel bars laid within the exterior walls of the building should be used as pressure equalization rings, and they should be connected to various vertical metal pipes and down conductors.

6. When the height of a building exceeds 30 meters, for the part of the building that is 30 meters and above, the railings, metal doors and windows and other large metal objects on the exterior walls should be connected to the lightning protection device.

The lightning protection design requirements for secondary lightning protection buildings

Like the first type a.b.c.d, the roof metal grid is no larger than 15m × 15m.

The lightning protection design requirements for Class III lightning protection buildings

Similar to the first level a.b.c.d, except that the roof metal grid is no larger than 20m × 20m.