Preface

TCVN 9310-4:2012 is completely equivalent to ISO 8421-4:2000.

TCVN 9310-4:2012 is converted from TCXDVN 216:1998 (ISO 8421-4:1990) according to the regulation in Clause 1 Article 69 of the Law on Standards and Technical Regulations and Point b) Clause 1 Article 7 of the Government’s Decree No. 127/2007/ND-CP dated August 1, 2007 detailing the implementation of some articles of the Law on Standards and Technical Regulations.

The TCVN 9310 Series under the general title “Fire Protection – Vocabulary” includes the following parts:

• TCVN 9310-3:2012 (ISO 8421-3:1989) Part 3: Fire detection and alarm.
• TCVN 9310-4:2012 (ISO 8421-4:1990) Part 4: Fire extinguishing equipment.
• TCVN 9310-8:2012 (ISO 8421-8:1990) Part 8: Terms specific to fire extinguishing, rescue services and handling of hazardous materials.

The ISO 8421 Series “Fire Protection – Vocabulary” also includes the following parts:

• ISO 8421-1:1987 Part 1: General terms and phenomena of fire.
• ISO 8421-2:1987 Part 2: Structural fire protection.
• ISO 8421-5:1988 Part 5: Smoke control.
• ISO 8421-6:1987 Part 6: Evacuation and means of escape.
• ISO 8421-7:1987 Part 7: Explosion detection and suppression means.

TCVN 9310-4:2012 is compiled by the Institute of Architecture, Urban and Rural Planning, proposed by the Ministry of Construction, appraised by the Directorate for Standards, Metrology and Quality, and published by the Ministry of Science and Technology.

1. Scope

This standard specifies terms and definitions related to:

• Fire extinguishing agents;
• Portable fire extinguishers;
• Fixed fire extinguishing systems.

General terms are given in ISO 8421-1. The terms in this standard are arranged in alphabetical order in English. The terms arranged in alphabetical order in English and French are given in the annex.

2. Normative references

The following referenced documents are indispensable for the application of this standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

TCVN 4878 (ISO 3941), Classification of fires.

ISO 7201:1982, Fire protection – Fire extinguishing media – Halogenated hydrocarbons.

ISO 8421-1:1987, Fire protection – Vocabulary – Part 1: General terms and phenomena of fire.

3. Terms and definitions

3.1. Fire extinguishing agents

3.1.1. Alcohol resistant aqueous film forming foam concentrate

Foam concentrate for use on fires of water-miscible liquids (polar liquids) and other fuels destructive to regular fire-fighting foams.

3.1.2. Aqueous film forming foam concentrate (AFFF)

Foam concentrate which, when mixed with water in the appropriate proportions, forms an aqueous film on the surface of certain hydrocarbons under specified conditions.

3.1.3. Burnback time

Time for fire to reappear over all or part of a fire area that has been covered by foam.

3.1.4. Carbon dioxide

Chemical compound CO₂ used as a fire extinguishing medium.

3.1.5. Chemical foam

Fire fighting foam produced by chemical reaction between alkaline salt solution and acid solution with a stabilizing agent.

3.1.6. Concentration ratio (of a foam solution)

Ratio of the volume of foam concentrate to the volume of the foam solution.

3.1.7. Critical application rate of foam solution

Theoretical minimum rate of application (3.1.24) of a foam solution required to control a fire.

3.1.8. Critical shear stress of foam

Minimum shear stress supported within the foam mass, the value of which is related to the foam viscosity, stability and fluidity.

3.1.9. Drainage time of foam

Time required to obtain a given proportion of liquid drained from a foam mass.

3.1.10. Expansion ratio of foam

Ratio of the volume of foam produced to the volume of foam solution used.

3.1.11. Fire fighting foam

Aggregate of air-filled bubbles formed from aqueous solutions of foam concentrates by means of specially designed equipment.

3.1.12. Fire fighting powder

Fire fighting medium consisting of finely divided products.

NOTE: The letters (A, B, C or D) are normally used after the term “Fire fighting powder” corresponding to the fire classification as defined in TCVN 4878.

3.1.13. Fluoroprotein foam concentrate

Protein foam concentrate (3.1.23) to which fluorochemical surface active agents have been added.

3.1.14. Foam compatibility

Ability for a foam to maintain its efficiency in the presence of another extinguishing agent (e.g. powder) on a fire.

3.1.15. Foam concentrate

Liquid which, when mixed with water in the appropriate concentration forms a foam solution.

3.1.16. Foam solution

Aqueous solution produced by mixing a foam concentrate and water in the proper proportions.

3.1.17. Halon

Halogenated hydrocarbon fire extinguishing agent (see ISO 7201).

NOTE: The following numbering system is used to designate halogenated hydrocarbons. The term “halon” is normally followed by a four-digit number indicating the number of the carbon, fluorine, chlorine and bromine atoms. None of these numbers is ever zero. For example, halon 1211 is bromochlorodifluoromethane (CF₂ClBr) and halon 1301 is bromotrifluoromethane (CF₃Br).

3.1.18. High expansion foam

Foam having an expansion ratio (3.1.10) greater than 200 (typically about 500).

3.1.19. Low expansion foam

Foam having an expansion ratio (3.1.10) less than 20 (typically about 10).

3.1.20. Mechanical (physical) foam

Fire fighting foam produced by introducing air or inert gas into a foam solution.

3.1.21. Medium expansion foam

Foam having an expansion ratio (3.1.10) between 20 and 200 (typically about 100).

3.1.22. Nominal application rate of foam solution

Rate of application of foam per unit area based on safety standards or the manufacturer’s specifications. The nominal application rate is often higher than the critical application rate.

3.1.23. Protein foam concentrate

Foam concentrate consisting primarily of products from a hydrolysis of proteinaceous materials.

3.1.24. Rate of application

Rate of discharge of foam solution per unit area of fire expressed in l/(m2 × min).

3.1.25. Synthetic foam concentrate

Foam concentrate based on foaming agents other than hydrolyzed proteins and including aqueous film forming foam (AFFF) concentrates.

3.1.26. Universal foam concentrate

Foam concentrate suitable for use on both water-miscible (polar solvent) liquids and hydrocarbons.

3.2. Portable fire extinguishers

3.2.1. Bursting pressure (of a fire extinguisher)

Internal pressure at which a fire extinguisher will be liable to burst due to failure of a component part.

3.2.2. Carbon dioxide fire extinguisher

Fire extinguisher containing carbon dioxide under high pressure as an extinguishing agent.

3.2.3. Complete discharge

Discharge of a fire extinguisher until the internal pressure balances with the atmospheric pressure, the control valve being fully opened.

3.2.4. Effective discharge time

Time from the commencement of discharge at the nozzle to the end of the discharge of useful extinguishing medium (but not necessarily the end of any propellant).

3.2.5. Filling density

Ratio of the mass of medium charged to the volume which the medium occupies inside a fire extinguisher or a cylinder filled with CO2 or other liquefied gas.

3.2.6. Fire extinguisher

Apparatus containing an extinguishing medium which can be expelled by the action of internal pressure and directed onto a fire.

3.2.7. Fire extinguisher, gas cartridge operated

Fire extinguisher in which the expellant gas is supplied from compressed or liquefied gas in a cartridge, opened at the moment of operation.

3.2.8. Fire extinguisher, (chemical) foam

Fire extinguisher discharging chemical foam when chemical solutions contained therein become intermixed and produce a chemical reaction.

3.2.9. Fire extinguisher, foam

Fire extinguisher containing a foam solution as fire extinguishing medium.

3.2.10. Fire extinguisher, halon

Fire extinguisher containing halon (3.1.17) for use as a clean extinguishing agent.

3.2.11. Fire extinguisher, hand

Portable fire extinguisher designed to be carried and operated by hand.

3.2.12. Fire extinguisher, powder

Fire extinguisher containing powder as an extinguishing medium.

3.2.13. Residual charge

Mass of extinguishing medium remaining in an extinguisher after complete discharge (3.2.3).

3.2.14. Working pressure (of a fire extinguisher)

Equilibrium pressure developed inside a fire extinguisher when it is charged and brought to its maximum permissible temperature.

3.2.15. Fire extinguisher, stored pressure

Fire extinguisher in which the extinguishing medium is permanently pressurized by the expellant.

3.2.16. Fire extinguisher, wheeled

Fire extinguisher mounted on wheels or castors.

3.2.17. Fire extinguisher, water

Fire extinguisher containing water with or without additives as an extinguishing medium.

3.3. Fixed fire extinguishing systems

3.3.1. General terms

3.3.1.1. Fixed fire-extinguishing system

Complete system of pipes, discharge nozzles and actuating device connected to one or several supplies of an extinguishing medium, which is permanently installed and automatically or manually operated.

3.3.1.2. Holding time

Time for which extinguishing medium must remain on site to effectively extinguish fire.

3.3.1.3. Local application system

Fixed fire extinguishing system with supply of an extinguishing medium arranged to discharge directly onto an object or hazard.

3.3.2. Fixed water and steam extinguishing systems

3.3.2.1. Area of operation

Maximum floor area over which it is estimated that sprinklers will operate and discharge water.

3.3.2.2. Automatic steam sprinkler system

System of pipes connected to a source of steam supply and fitted with sprinklers at suitable heights and intervals; when a sprinkler operates, steam automatically discharges from that sprinkler.

3.3.2.3. Branch system

System in which sprinkler-supporting pipes (3.3.2.10) are supplied with water only in one direction from a sub-main or main.

3.3.2.4. Deluge system

System of open sprinklers attached to a water piping system connected to a water supply through a valve which is opened by the operation of a detection system installed in the same area as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.

3.3.2.5. Drencher

Water sprinkler fitted to a pipe or system of pipes for discharging water on to a surface to be protected from exposure to fire.

3.3.2.6. Drencher system

Fixed fire extinguishing system in which open water sprinklers are installed at suitable heights and intervals in piping connected to a water supply to discharge water over a surface to be protected from exposure to fire.

3.3.2.7. End-centre arrangement

Arrangement of the pipe system of a sprinkler installation in which the sprinkler-supporting pipes (3.3.2.10) are spaced so that sprinklers are located alternatively along each side of the branch.

3.3.2.8. End-side arrangement

Arrangement of the pipe system of a sprinkler installation in which the sprinkler-supporting pipes (3.3.2.10) are parallel and are spaced so that sprinklers appear on one side only of each branch.

3.3.2.9. Gridded system

Sprinkler system in which sprinkler-supporting pipes (3.3.2.10) are supplied with water from each end.

3.3.2.10. Sprinkler-supporting pipe

Main or range pipe on which sprinklers are directly mounted either directly or on short pieces of pipe.

3.3.2.11. Loop system

Sprinkler system in which main pipes form a closed ring.

3.3.2.12. Sprinkler

Heat sensitive device designed to react at a predetermined temperature by automatically releasing a stream of water and distributing it in a specified pattern and quantity over a designated area.

3.3.2.13. Sprinkler, concealed

Sprinkler with its operating components contained within a recess and covered by a cap.

3.3.2.14. Sprinkler, conventional (old style or old pattern)

Sprinkler having a spherical discharge pattern in which water is first directed upwards and then downwards towards the generally horizontal plane by means of a deflector; from 40 % to 60 % of the total water discharge initially flows downwards.

3.3.2.15. Sprinkler, dry type

Complete assembly of a sprinkler and extension nipple, used to prevent water from entering the nipple until the sprinkler operates.

3.3.2.16. Sprinkler, flush

Sprinkler having a parabolic discharge pattern in which water is discharged in an umbrella shaped pattern below a generally horizontal plane; from 60 % to 80 % of the total water discharge flows downwards.

3.3.2.17. Sprinkler, flush mounted type

Sprinkler in which part or all of the heat responsive portion, including the threaded part, is mounted above the lower plane of the ceiling.

3.3.2.18. Sprinkler, fusible element type

Sprinkler operated by the melting of a fusible element.

3.3.2.19. Sprinkler, glass-bulb type

Sprinkler operated by bursting of a glass bulb under the pressure of a liquid within the bulb expanded by heat.

3.3.2.20. Sprinkler, horizontal

Sprinkler designed to be installed so that the water stream is discharged in a horizontal direction.

3.3.2.21. Sprinkler, pendent

Sprinkler designed to be installed so that the water is directed downward against a deflector.

3.3.2.22. Sprinkler, recessed type

Sprinkler, except for the threaded end, contained within a recessed housing.

3.3.2.23. Sprinkler, side-wall type

Sprinkler in which water is discharged to one side only in a generally parabolic pattern.

3.3.2.24. Sprinkler, spray type (old style or old pattern)

Sprinkler in which water is discharged in a parabolic pattern below a generally horizontal plane and having 80 % to 100 % of the total water initially flowing downward; the sprinkler may be either pendent or upright.

3.3.2.25. Sprinkler, upright

Sprinkler designed and installed so that the water is directed upward and then deflected downward by a deflector.

3.3.2.26. Sprinkler alarm valve

Check valve which is designed to allow water supply to a sprinkler system and to actuate an alarm on commencement of water flow.

3.3.2.37. Water spray jet device

Nozzle connected to a water pipe and designed to discharge water in the form of a jet at high pressure.

3.3.2.38. Water spray jet system

System of water pipes fitted with water spray jet devices (3.3.2.38) and equipment for fire fighting operation.

3.3.3. Fixed fire extinguishing systems (non-water)

3.3.3.1. Sub-surface application device

Device for introducing foam beneath the surface of flammable liquid in such a way that the foam rises and spreads over the surface to form a fire fighting foam blanket.

3.3.3.2. Carbon dioxide (CO₂) fire extinguishing system

Fixed fire extinguishing system using carbon dioxide as the extinguishing medium.

3.3.3.3. Combined agent fire extinguishing system

Fire extinguishing system using more than one fire extinguishing agent (e.g. foam and powder) and operated manually or automatically.

3.3.3.4. Foam fire extinguishing system

Fixed fire extinguishing system using foam as the extinguishing medium.

3.3.3.5. Foam solution transit time

Time for foam solution to pass through the pipework from the point of injection of the foam concentrate into the water stream to the air injection point where foam is generated.

3.3.3.6. Halon fire extinguishing system

Fixed fire extinguishing system using a halon as the extinguishing medium.

3.3.3.7. Inert gas fire extinguishing system

System designed to establish a concentration of inert gas sufficient to prevent ignition of the flammable or explosive atmosphere by reduction of the oxygen content of that atmosphere below the limits of flammability or explosibility.

3.3.3.8. Inductor for foam concentrate

Device designed to introduce foam concentrate into the water stream, usually placed between the pump and the delivery hose.

3.3.3.9. Foam generator (mechanical foam generating equipment)

Device for introducing foam concentrate into the water stream to produce a foam solution and entraining air under pressure into the foam solution to generate foam.

3.3.3.10. Powder fire extinguishing system

Fixed fire extinguishing system using powder as the extinguishing medium.

3.3.3.11. Self-inducing foam branchpipe

Foam generator in which air induction is achieved by spraying the foam solution from a nozzle through a venturi. The entrained air is then mixed with the foam solution by the energy of the foam generator.

3.3.3.12. Total flooding with extinguishing medium

Achievement of a concentration of extinguishing medium (gas, high expansion foam) throughout an enclosure sufficient to extinguish a fire within that enclosure.

3.3.3.13. Total flooding fire extinguishing system

Fixed fire extinguishing system for the extinction of fires in an enclosed protected area.

3.4. Fire hoses

3.4.1. Hose reel

Type of hose container (3.4.2) in which the hose is wound on a reel and is semi-rigid.

3.4.2. Hose container

Container consisting of a fire-fighting hose connected to a nozzle and to a shut-off valve, with suitable support.

3.4.3. Underground hydrant

Hydrant with below-ground operating facilities covered by a pit cover or surface box and permanently connected to a water main under pressure for fire-fighting use.

3.4.4. Above ground hydrant

Hydrant comprising one or more outlets mounted above ground level and permanently connected to a water main under pressure for fire-fighting use.

3.4.5. Dry riser

Permanently installed pipe capable of being connected to a water supply to provide water for fire-fighting within a building.

3.4.6. Wet riser

Permanently installed pipe connected to a pressurized water supply to provide water for fire-fighting through landing valves within a building.