I. Building Fire Resistance Rating

1. Buildings are classified into four fire resistance grades, namely Grade 1, Grade 2, Grade 3 and Grade 4.
2. Fire protection layers shall be applied to joint gaps and exposed parts of joints on load-bearing metal components.
3. For civil buildings of Grade 1 and Grade 2 fire resistance, the maximum length of each fire compartment is 250 meters, and the maximum allowable floor area is 2500 square meters.
4. Mechanical smoke exhaust facilities shall be installed for underground rooms, windowless rooms, above-ground rooms with fixed sashes, evacuation corridors longer than 20 meters without natural smoke exhaust, and internal evacuation corridors with direct natural ventilation but exceeding 40 meters in length.

5. Smoke Exhaust Requirements

II. Building Fire Compartments, Fire Separation Distances and Evacuation Exits

1. Where connecting openings such as overhead walkways and escalators exist between adjacent floors inside a building, the interconnected floors shall be regarded as one single fire compartment.
2. Fire compartments in underground and semi-underground buildings shall be separated by fire walls, and the floor area of each fire compartment shall not exceed 500 m².
3. Where automatic fire extinguishing systems are installed, the maximum allowable floor area of each fire compartment can be increased to 1000 m². For partial installation of such systems, the increased area shall be twice the area of the installed part.
4. The fire separation distance between civil buildings shall be 6 to 9 meters.
5. Public buildings and corridor-type residential buildings shall be equipped with no less than two safety exits.
6. Tower-type residential buildings with no more than nine floors and a total floor area not exceeding 500 m² may be provided with only one staircase.
7. High-rise buildings must be equipped with two safety exits.
8. Safety exits and evacuation exits in buildings shall be arranged in a dispersed manner. The horizontal distance between the nearest edges of two adjacent safety or evacuation exits shall not be less than 5.0 meters.
9. For doors directly leading to public corridors, the maximum distance to the nearest external exit or enclosed staircase is 25 meters for buildings of Grade 1 and Grade 2 fire resistance, and 22 meters for loop corridors. The evacuation distance may be increased by 25% for buildings installed with automatic sprinkler systems.
10. The ground floor of a staircase shall have a direct external exit. For buildings with no more than four floors, the external exit may be located within 15 meters from the staircase.
11. Emergency exit doors shall be outward opening push-bar doors.
12. Fire walls shall be constructed between transformer rooms and power distribution rooms. Boiler rooms and transformer rooms shall be arranged on the ground floor adjacent to external walls and fitted with outward opening doors. A fire cornice with a width of no less than 1.00 meter or windows with a height of no less than 1.50 meters shall be installed above openings on external walls of the ground floor.

III. Outdoor Fire Hydrant System

1. Where fire lanes pass through building doorways, the clear height and clear width shall not be less than 4 meters; the clear width between door piers shall not be less than 3.5 meters.
2. Pipe shafts and cable shafts inside buildings shall be sealed with non-combustible materials having a fire resistance limit of no less than 0.50 hours at floor slabs every 2 to 3 floors. The shaft walls shall be constructed of non-combustible materials with a fire resistance limit of no less than 1.00 hour. Inspection doors on shaft walls shall be Class C fire doors.
3. Walls of elevator shafts and elevator machine rooms shall be made of non-combustible materials with a fire resistance limit of no less than 1 hour. For indoor elevator shafts and elevator machine rooms in high-rise industrial buildings, the fire resistance limit of wall materials shall not be less than 2.5 hours.
4. The height of handrails on evacuation staircases shall not be less than 1.1 meters. For external staircases of other buildings, the inclination angle shall not exceed 60 degrees, and the clear width shall not be less than 0.8 meters. This requirement may be waived if the tread depth exceeds 0.88 meters at a position 0.25 meters away from the handrail.
5. Fire water can be supplied by water supply pipe networks, natural water sources or fire water tanks.
6. The effective water column of nozzles for outdoor fire hydrants shall be no less than 10 meters measured from the ground.
7. The water flow rate for outdoor fire hydrants of civil buildings shall be guaranteed at 30 L/s.
8. At least two main water supply pipes shall be used for loop pipe networks and water delivery pipes feeding into loop networks.
9. Loop pipelines shall be divided into several independent sections by valves, and each section shall contain no more than 5 fire hydrants. The minimum diameter of outdoor fire water supply pipes shall not be less than 100 mm.
10. Outdoor fire hydrants shall be installed along roads. For roads wider than 60 meters, hydrants are recommended to be installed on both sides close to road intersections.
11. The distance from an outdoor fire hydrant to the road edge shall not exceed 2 meters, and the distance to external building walls shall not be less than 5 meters.
12. The spacing between outdoor fire hydrants shall not exceed 120 meters, and the protection radius of each outdoor fire hydrant shall not exceed 150 meters.
13. The water flow rate of each outdoor fire hydrant shall be calculated as 10 to 15 L/s, and the flow rate for fire pump adapters shall also be 10 to 15 L/s.
14. The effective water column of fire hydrants in high-rise buildings shall range from 10 meters to 13 meters.
15. Above-ground outdoor fire hydrants shall be equipped with one outlet of 150 mm or 100 mm diameter and two outlets of 65 mm diameter.
16. The water storage capacity of fire water tanks shall be calculated based on a 1-hour duration of automatic sprinkler operation.
17. The minimum volume of Class 1 fire water tanks is 18 cubic meters, and 12 cubic meters for Class 1 residential buildings.
18. The protection radius of fire water tanks for fire truck water intake shall not exceed 150 meters. A water intake shall be provided, and the distance between the intake and buildings (excluding pump rooms) shall not be less than 15 meters.

IV. Indoor Fire Hydrant System

1. The standard water flow rate of indoor fire hydrants for civil buildings is 20 L/s, with no fewer than 4 hydrants installed. For buildings over 50 meters high, the flow rate is 10 L/s, and 30 L/s for super high-rise buildings.

   

2. Where there are more than 10 indoor fire hydrants and the total indoor fire water flow rate exceeds 15 L/s, the indoor fire water supply pipes shall be connected to the outdoor loop network via at least two inlet pipes. The indoor pipes or inlet pipes shall be arranged in a loop. In case one inlet pipe fails, the remaining pipes shall still be able to deliver the full required water volume.
3. Indoor fire risers in high-rise industrial buildings shall be arranged in a loop with a pipe diameter of no less than 100 mm.
4. Indoor fire water supply pipes shall be divided into several independent sections by valves.
5. Indoor fire hydrants shall be arranged to ensure that any spot inside the building can be reached by the effective water columns of two fire nozzles simultaneously. The spacing between adjacent indoor fire hydrants shall not exceed 25 meters, and the effective water column of each nozzle shall be no less than 13 meters.
6. The static water pressure at indoor fire hydrant outlets shall not exceed 80 meters water column. Zoned water supply systems shall be adopted if the pressure exceeds this limit. Pressure relief devices shall be installed where the outlet water pressure exceeds 50 meters water column.
7. Indoor fire hydrants shall be installed in the antechamber of fire elevators. The outlet shall be 1.1 meters above the ground, and the water discharge direction shall face downward or form a 90-degree angle with the wall.
8. The spacing between fire hydrants on the same floor shall not exceed 30 meters. Each hydrant outlet is 1.1 meters above the ground with a DN65 interface. The fire hose shall be no less than 25 meters long, and the nozzle diameter is 20 mm.
9. The fire water tank shall reserve water for 10 minutes of fire fighting. If the calculated required tank volume exceeds 12 m³ when the indoor fire water flow rate is no more than 25 L/s, a 12 m³ tank is still acceptable. If the calculated volume exceeds 18 m³ when the flow rate is over 25 L/s, an 18 m³ tank shall be adopted.

V. Automatic Sprinkler System

45. Automatic sprinkler systems shall be installed for underground shops with an area larger than 500 m².
46. An automatic sprinkler system consists of alarm valves, control valves, water-powered alarm gongs, system test devices, pressure gauges, on-off indicators, flow indicators, pressure switches and auxiliary electric alarm devices.
47. Alarm valves shall be installed 1.2 meters above the ground.
48. The maximum number of sprinkler heads controlled by one alarm valve is 800 for wet and pre-action systems, 50 for dry systems with exhaust devices, and 250 for dry systems without exhaust devices.
49. The diameter of fire branch pipes shall not be less than 25 mm, and each branch pipe shall serve a maximum of 8 sprinkler heads.

VI. Fire Water Pumps

1. Each set of fire water pumps shall be equipped with no less than two suction pipes. Overpressure protection measures shall be installed for high-rise buildings.
2. The fire pump room shall have no less than two outlet pipes directly connected to the loop pipe network.
3. Standby pumps shall be provided for fixed fire water pumps, with a capacity no less than that of the main pump.
4. Fire water pumps shall start operation within 5 minutes after a fire alarm and keep running normally in case of power failure on site.

VII. Fire Protection Design for Electromechanical Disciplines

1. Where the ventilation and air conditioning systems of each fire compartment on all floors of multi-storey buildings and high-rise industrial buildings are independently installed, fire dampers may be omitted at the joints between horizontal supply/return air ducts and main ducts within the protected fire compartment.
2. Storage batteries may be used as standby power supplies for emergency lighting and evacuation indicator signs, with a continuous power supply duration of no less than 20 minutes.
3. Emergency lighting shall be installed in enclosed staircases, smoke-proof staircases and their antechambers, as well as the antechambers of fire elevators.
4. Emergency lighting shall also be fitted in evacuation corridors of buildings required to have enclosed or smoke-proof staircases.
5. The minimum illuminance of emergency lighting for evacuation shall not be lower than 0.5 lx. Lighting branch circuits in fire control rooms, fire pump rooms and self-provided generator rooms shall be connected to fire power distribution lines.
6. Evacuation indicator signs shall be mounted above emergency exit doors or on walls below 1 m above the ground along evacuation corridors and their corners.

   

   The spacing between adjacent signs on corridors shall not exceed 20 m.

VIII. Automatic Fire Alarm System and Fire Control Room

1. Alarm zones shall be divided in accordance with fire compartments, and one alarm zone may consist of multiple fire compartments.
2. Automatic fire alarm systems are categorized into centralized alarm systems, regional alarm systems and fire control systems (fire control centers). A regional alarm controller can monitor multiple floors subject to product specifications. It shall be installed 1.3 m to 1.5 m above the ground, and fire alarm telephones shall be mounted at the same height.
3. Automatic fire alarm devices shall be installed in underground shops with a floor area larger than 500 m².
4. A standalone fire control room shall have a fire resistance rating of no less than Grade 2. It shall be separated from other areas by partition walls with a fire resistance limit of no less than 3 hours and floor slabs with a fire resistance limit of no less than 2 hours, and shall be equipped with a direct external safety exit.
5. The fire control room shall be capable of receiving fire alarms, activating audible and visual fire signals, issuing emergency broadcasts and evacuation instructions; controlling fire water pumps, fixed fire extinguishing systems, ventilation and air conditioning systems, motorized fire doors, dampers, fire roller shutters as well as smoke prevention and exhaust facilities; and displaying the operating status of power supplies and fire elevators.
6. Manual fire alarm buttons shall be installed 1.5 m above the ground.
7. Fire alarm wires shall be reserved with an extra length of 100 mm to 200 mm and bundled together, using red and blue conductors.
8. Fire alarm wires shall be laid without joints or twists. All wire connections shall be made via terminals or welding inside junction boxes, with no more than two wires connected to each terminal. Nuts shall be fitted both inside and outside the boxes. Wires of different voltages, currents, circuits, systems and categories shall not be routed in the same trunking.
9. Hangers and supports shall be installed for trunking at intervals of 1.5 m, and the diameter of hanging rods shall not be less than 6 mm.
10. Fire power supplies shall be dedicated circuits with no plug-in connections allowed.
11. The door of the fire control room shall open towards the evacuation direction. Supply and return air ducts are permitted to pass through the room, provided that fire dampers are installed. No irrelevant electrical circuits shall be routed across the room. A passageway of 1 m wide shall be reserved around the control console for operation and maintenance.
12. Functions of fire control equipment: starting and stopping fire-fighting devices; switching on and off fire water pumps, smoke prevention and exhaust fans; closing fire dampers and shutting down air supply fans of air conditioning systems; displaying locations of fire and fault alarms, evacuation passages and exits; displaying protection drawings including schematic diagrams and floor plans; monitoring the status of fire power supplies; and being equipped with emergency broadcast control devices for fire alarms.
13. Operating sequence upon fire occurrence: The automatic fire alarm system triggers an alert, followed by activation of automatic fire extinguishing systems and indoor fire hydrant systems together with fire water pumps. Power supply is switched over: non-fire power supplies are cut off while emergency fire power supplies are activated. Alarm devices, emergency lighting and evacuation indicator lights are energized. All elevators are forced to stop at the ground floor. Pressurization air fans and their outlets are activated, isolation systems such as fire roller shutters are deployed, and fire doors are closed.
14. At least one manual fire alarm device shall be installed in each fire compartment. The spacing between two adjacent manual alarm devices shall not exceed 30 m, and they shall be mounted 1.3 m to 1.5 m above the ground.

IX. Smoke Prevention and Exhaust Systems

1. Smoke compartments shall be established for Grade 1 and Grade 2 buildings over 50 m high and all buildings with a height exceeding 32 m.
2. The area of a single smoke compartment shall generally not exceed 500 m². A smoke compartment shall be smaller than or equal to a fire compartment and shall not cross fire compartment boundaries. Dedicated independent duct systems shall be installed for corridors, smoke shafts and exhaust shafts respectively, with a fire resistance limit of 1 hour.
3. Smoke prevention and exhaust systems for high-rise buildings include mechanical pressurization smoke prevention systems and automatic smoke exhaust systems with operable external windows. The automatic smoke exhaust systems are further divided into mechanical smoke exhaust systems and natural smoke exhaust systems with operable external windows.

   

4. Tower buildings shall be equipped with two smoke-proof evacuation staircases with independent antechambers fitted with mechanical pressurization air supply systems. Pressurization air outlets shall be installed every 2 to 3 floors in staircases and on every floor in antechambers.
5. The designed air volume for smoke-proof staircases and shared fire antechambers ranges from 18000 to 20000 m³/h and 28000 to 30000 m³/h respectively. For buildings with more than 32 floors, the air volume shall be calculated by sections.

(I) Mechanical Pressurization Air Supply System

1. Mechanical pressurization air supply systems shall be installed for antechambers, staircases, shared antechambers and fire elevator antechambers. Where pressurization systems for staircases and fire antechambers have to be combined, automatic differential pressure regulating devices shall be installed. After deducting the pressure loss at the most unfavorable point, the residual total pressure of the system shall comply with relevant regulations.
2. The designed differential pressure for smoke-proof staircases is 50 Pa.
3. The designed differential pressure for antechambers, staircases, shared antechambers, fire elevator antechambers and refuge rooms is 25 Pa.
4. Pressurization air outlets shall be arranged every 2 to 3 floors in staircases and on each floor in antechambers.
5. Air velocity requirements for mechanical pressurization and smoke exhaust systems:
   
   5.1 The air velocity in metal ducts shall not exceed 20 m/s.
   
   5.2 The air velocity in concrete ducts shall not exceed 15 m/s.
   
   5.3 The air velocity at air supply outlets shall not exceed 7 m/s, and the air velocity at smoke exhaust outlets shall not exceed 10 m/s.
6. Smoke exhaust systems shall be installed for staircases, antechambers, fire antechambers, shared antechambers and refuge floors.
7. The air supply and exhaust volume for staircases in buildings with more than 32 floors shall be calculated by sections.
8. A single duct may serve two staircases in shear wall buildings, with the total air volume calculated for two staircases and separate outlets installed accordingly.
9. The pressurization air volume for refuge floors shall be no less than 30 m³/s based on net floor area. Each refuge floor shall be equipped with fire elevator exits, emergency lighting, broadcast systems, fire telephones and fire hydrants, as well as independent smoke prevention facilities and partitioned smoke-proof staircases.

(II) Mechanical Smoke Exhaust (Smoke Prevention) System

1. Installation criteria for smoke exhaust systems:
   
   1.1 Building height exceeds 32 m.
   
   1.2 Internal corridors longer than 20 m are equipped with natural lighting and natural ventilation facilities.
   
   1.3 Room area exceeds 100 m².
   
   1.4 Ventilation and air conditioning systems shall be fitted with smoke exhaust systems.
2. Installation requirements for smoke prevention systems:
   
   2.1 For rooms with a clear height over 6 m covering one smoke compartment, the exhaust air volume shall be no less than 60 m³ per square meter.
   
   2.2 For rooms with a clear height over 6 m covering one smoke compartment, the exhaust air volume shall be no less than 120 m³ per square meter.
   
   2.3 Smoke exhaust outlets shall be installed on roofs and ceilings, with an exhaust volume no less than 60 m³/s.
   
   2.4 The horizontal spacing between smoke prevention outlets shall not exceed 30 m, and the closing temperature of smoke prevention dampers is 280°C.
   
   2.5 Vertical smoke prevention and exhaust ducts shall be arranged for corridors, while those inside rooms shall be arranged by individual fire compartments.
   
   2.6 Mechanical smoke prevention and exhaust systems may be combined with ventilation and air conditioning systems, provided that reliable fire protection measures are adopted.
   
   2.7 Fire-resistant ducts serve as life safety systems for buildings, mainly for smoke exhaust and pressurized air supply during fires. They are classified by fire resistance ratings such as 1-hour, 2-hour and 4-hour.
3. Ventilation and air conditioning systems:
   
   3.1 Ventilation systems shall be arranged horizontally by fire compartments and vertically every five floors at maximum.
   
   3.2 Fire dampers with a closing temperature of 70°C shall be installed where ventilation and air conditioning ducts pass through fire compartment walls, floor slabs and expansion joints.

X. Miscellaneous Provisions

1. Curtain walls shall have a fire resistance rating of 1 hour.
2. Fire protection layers shall be applied to building expansion joints.
3. Frameless glass curtain walls and spaced glass curtain walls shall have a fire resistance rating of 1 hour and be fitted with solid walls of no less than 800 mm in height.
4. The oil storage capacity of generator rooms shall not exceed the consumption for 8 hours of operation.
5. The minimum spacing between high-rise buildings is 13 m, and 6 m between podium buildings.
6. Fire lanes shall have a clear width of no less than 4 m, a clear height of no less than 4 m, and maintain a distance of no less than 5 m from buildings.
7. Fire protection layers shall be applied to building expansion joints and metal structures.
8. For Grade 1 and Grade 2 buildings, the maximum length of a single fire compartment is 150 m and the maximum floor area is 2500 m².

XI. Fire Compartment Division

1. Maximum floor area of a single fire compartment: 1000 m² for Grade 1 buildings, 1500 m² for Grade 2 buildings, and 500 m² for basements.
2. Where fire walls and effective fire protection measures are installed between a high-rise building and its podium building, the maximum floor area of each fire compartment shall not exceed 2500 m².