GB 50057-2010 Code for Design Protection of Structures Against Lightning

General Provisions

• 第 1.0.1 条This code applies to the lightning protection design of new, extended, and renovated buildings. Hotel buildin…
• 第 1.0.2 条Lightning protection design should be adapted to local conditions and adopt comprehensive measures. Hotel bui…
• 第 1.0.3 条Buildings shall be classified into Class I, Class II, and Class III lightning protection categories based on …
• 第 1.0.4 条Lightning protection design should be safe, reliable, technologically advanced, and economically rational. Th…
• 第 1.0.5 条Lightning protection design for new hotel buildings should be integrated into the overall design and coordina…
• 第 1.0.6 条Lightning protection design shall, in addition to complying with this code, also comply with the provisions o…
• 第 第4.2.1条 条Second class lightning protection building: down conductor spacing not greater than 18m ();
• 第 第4.2.1条 条Class III lightning protection building: the spacing between down conductors shall not exceed 25m ();
• 第 第5.2.1条 条Metal flagpoles, antennas, etc. on the hotel roof should serve as air termination systems, with a diameter of…

Terminology

• 第 2.0.1 条Air termination system : A device composed of air termination rods, air termination strips, air termination w…
• 第 2.0.2 条Down conductor : A conductor used to carry lightning current from the air termination system to the grounding…
• 第 2.0.3 条Grounding device : The general term for grounding electrodes and grounding conductors buried in soil or concr…
• 第 2.0.4 条Lightning protection system : A general term for the complete assembly consisting of air termination system, …
• 第 2.0.5 条Lightning Protection Zone (LPZ) : Zones divided according to the severity of lightning electromagnetic pulses…
• 第 2.0.6 条Surge Protective Device (SPD) : A device used to limit transient overvoltages and discharge lightning current…
• 第 2.0.7 条Equipotential bonding : Directly connect separate metal objects with conductors to eliminate potential differ…
• 第 2.0.8 条Lightning protection equipotential bonding : Bond the lightning protection system to metal objects, electrica…
• 第 2.0.9 条Lightning protection grounding : A device that provides a good connection between the lightning protection sy…
• 第 2.0.10 条Lightning protection classification : Based on the importance and use of the building, and the likelihood and…

Classification of lightning protection for buildings

• 第 3.0.3 条In areas where lightning strikes to ground may occur, a building shall be classified as a Class II lightning …
• 第 3.0.4 条In areas where lightning strikes to ground may occur, a building shall be classified as a Class III lightning…
• 第 3.0.2 条A building shall be classified as a Class I lightning protection building if any of the following conditions …
• 第 0.05 条Note : The specific lightning protection classification of a hotel building shall be determined based on its …

Lightning protection system

• 第 4.2.1 条Air termination system layout : For a Class II lightning protection hotel building, the rolling sphere radius…
• 第 4.3.1 条Down conductor spacing : For Class II lightning protection hotel buildings, the average spacing of down condu…
• 第 4.3.5 条Grounding device : When the lightning protection grounding shares a grounding device with the electrical syst…
• 第 4.5.2 条Protection against lightning surge intrusion : For all low voltage distribution lines and signal lines (such …
• 第 5.2.1 条Air termination material : For air termination rods (lightning rods) made of hot dip galvanized round steel, …
• 第 5.3.1 条Down conductor material : For exposed down conductors using hot dip galvanized round steel, the diameter shal…
• 第 5.4.2 条Grounding electrode materials : When hot dip galvanized angle steel is used for artificial vertical grounding…
• 第 6.1.2 条Surge Protective Device (SPD) Selection : For power supply line SPDs serving electronic information systems i…

Lightning protection device

• 第 4.4.3 条Equipotential bonding : All metal pipes, cable metal sheaths, building metal components, etc. entering or exi…
• 第 4.5.1 条Side flash lightning protection : For a Class II lightning protection hotel building exceeding 30m in height,…

Air termination

• 第 5.2.1 条An air termination system shall consist of one or a combination of the following: isolated air termination ro…
• 第 5.2.4 条Air termination strips should be installed on parts of the building susceptible to lightning strikes (such as…
• 第 5.2.5 条Air termination network mesh size requirements: For Class II lightning protection buildings (a common categor…
• 第 5.2.6 条Material requirements for air termination rods (lightning rods): when round steel is used, the diameter shall…
• 第 5.2.7 条Air termination systems shall be hot dip galvanized or painted for corrosion protection. In highly corrosive …
• 第 5.2.8 条Spacing of supports (brackets) for air termination strips (mesh): the horizontal straight section should be 0…
• 第 5.2.9 条When metal objects (such as metal railings, billboards, solar water heaters, outdoor air conditioning units, …
• 第 5.2.10 条The connection between the air termination and the down conductor shall be made by welding or clamp connector…
• 第 5.2.12 条When a metal roof is used on a hotel roof, if the metal panel thickness is not less than 0.5mm (iron) or 0.4m…

Down conductor

• 第 4.3.3 条There shall be no fewer than 2 dedicated down conductors, arranged evenly and symmetrically around the perime…
• 第 4.3.5 条When using building reinforcement as down conductors, if the rebar diameter is ≥16 mm, 2 rebars (tied or weld…
• 第 4.3.6 条Down conductors should preferentially use the reinforcement in the building's reinforced concrete or steel st…
• 第 4.3.7 条When round steel is used for down conductors, the diameter shall not be less than 8 mm; when flat steel is us…
• 第 4.3.8 条Down conductors should be installed exposed along the building's exterior walls and grounded via the shortest…
• 第 4.3.9 条When multiple down conductors are used, a test joint shall be installed on each down conductor at a height of…
• 第 4.4.3 条(For Class III lightning protection buildings) There shall be no fewer than 2 dedicated down conductors, arra…
• 第 4.4.5 条(For Class III lightning protection buildings) When round steel is used for down conductors, the diameter sha…
• 第 5.2.4 条(Grounding system) Lightning protection grounding, electrical equipment grounding, and information system gro…
• 第 第3.0.3条 条Hotel buildings are typically designed as Class II lightning protection structures (per the standard, public …

Grounding device

• 第 4.2.1 条Grounding device materials and minimum dimensions : The grounding electrodes of hotel buildings shall use hot…
• 第 4.2.2 条Grounding resistance value : When the lightning protection grounding device of a hotel building is shared wit…
• 第 4.3.1 条Buried depth of grounding electrodes : The length of an artificial vertical grounding electrode should be 2.5…
• 第 4.3.2 条Grounding electrode spacing : The horizontal distance between vertical grounding electrodes should preferably…
• 第 4.3.3 条Ring grounding electrode : For hotel buildings, the foundation reinforcement should preferably be used as a n…
• 第 4.3.4 条Equipotential bonding : All metal pipes, cable metal sheaths, elevator rails, metal doors and windows, etc. e…
• 第 4.3.5 条Protection against step voltage and touch voltage : In areas with frequent guest activity (e.g., entrances, p…
• 第 4.3.6 条Grounding device connections : Connections between grounding electrodes must be welded (overlap length: 6 tim…
• 第 4.4.1 条Test point setup : The hotel building shall be provided with no fewer than 2 earthing resistance test points …

Equipotential bonding

• 第 6.2.2 条All metal pipes, metal cable sheaths, and metal conduits of power lines entering or leaving the hotel buildin…
• 第 6.2.4 条The equipotential bonding conductors (MEB) on each floor of the hotel (such as guest room floors, the lobby, …
• 第 6.3.1 条All conductive metal objects in the hotel (such as metal doors and windows, metal suspended ceilings, elevato…
• 第 6.3.2 条Exposed conductive parts of electrical installations in the hotel (such as distribution box enclosures, socke…
• 第 6.3.3 条Equipotential bonding for information equipment within the hotel (such as the ELV equipment room, fire contro…
• 第 6.3.4 条Local equipotential bonding terminal boxes (LEB) shall be installed in hotel bathrooms (especially shower and…
• 第 6.3.5 条Equipotential bonding for the swimming pool and SPA area (if any) within the hotel: all metal components (suc…
• 第 6.3.6 条Guide rails, car metal structures, and elevator control cabinet enclosures within the elevator shaft in the h…
• 第 6.4.1 条The total resistance of the bonding conductor between the lightning protection equipotential bonding bar and …

Lightning electromagnetic pulse

• 第 6.1.2 条Electronic information systems in hotel buildings (such as fire alarm, security surveillance, communication n…
• 第 6.2.1 条When the hotel building is equipped with an electronic information system, an equipotential grounding network…
• 第 6.2.2 条All metal pipelines entering the building within the hotel (such as metal cable sheaths, water pipes, gas pip…
• 第 6.3.1 条Surge protective devices (SPDs) shall be installed on hotel power supply lines. At the boundary between LPZ0A…
• 第 6.3.2 条Power ports of critical equipment in the hotel (such as computers, servers, and fire control hosts) shall be …
• 第 6.3.4 条Signal line SPDs shall be installed for hotel signal lines (such as network, telephone, and cable TV), with a…
• 第 6.4.1 条The shielding of electronic information system equipment rooms in hotel buildings shall comply with the follo…
• 第 6.4.2 条Weak current wiring in the hotel (such as structured cabling) shall be installed in metal conduits or metal c…
• 第 6.5.1 条The grounding of electronic information systems in the hotel shall adopt a common grounding system, and the g…

Engineering reference only — verify against project conditions and the latest codes.