Buildings should be divided into three categories according to their importance, nature of use, possibility and consequences of lightning accidents, and protection requirements.

In areas where lightning strikes to the ground may occur, if one of the following situations occurs, it should be classified as a Class I lightning protection building:

1. Dangerous buildings used for the manufacture, use or storage of explosives and their products may explode or detonate due to electric sparks, causing huge damage and casualties.

2. Buildings with Zone 0 or Zone 20 explosion hazard areas.

3. Buildings with Zone 0 or Zone 20 explosion hazard areas.

In areas where lightning strikes to the ground may occur, if one of the following situations occurs, it should be classified as a Class II lightning protection building:

1. Buildings under national key cultural relic protection.

2. National halls, office buildings, large exhibition and expo buildings, large railway stations and airports, state guesthouses, national archives, important water supply pump houses in large cities and other particularly important buildings.

Note: Airports do not include open areas and runways for parking aircraft.

3. National computing centers, international communication hubs, and other buildings that are important to the national economy.

4. National special and first-class large stadiums.

5. Dangerous buildings used for the manufacture, use or storage of explosives and their products, where electric sparks are unlikely to cause explosions or cause huge damage and casualties.

6. Buildings with explosion hazard areas in Zone 1 or Zone 21 where electric sparks are unlikely to cause explosions or cause huge damage and casualties.

7. Buildings with Zone 2 or Zone 22 explosion hazard areas.

8. Steel closed gas tanks with explosion risk in open air.

9. Ministry and provincial office buildings and other important or densely populated public buildings and fire-hazardous places where the number of lightning strikes is expected to be greater than 0.05 times/a.

10. General civil buildings such as residential buildings, office buildings, or general industrial buildings where the number of lightning strikes is expected to be greater than 0.25 times/a.

In areas where lightning strikes to the ground may occur, if one of the following situations occurs, it should be classified as a Class III lightning protection building:

1. Provincial key cultural relics protection buildings and provincial archives.

2. Ministry and provincial-level office buildings and other important or densely populated public buildings, as well as fire-hazardous places, where the number of lightning strikes is expected to be greater than or equal to 0.01 times/a and less than or equal to 0.05 times/a.

3. General civil buildings such as residential buildings and office buildings, or general industrial buildings where the expected number of lightning strikes is greater than or equal to 0.05 times/a and less than or equal to 0.25 times/a.

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