---

n) enclosure pressurization and venting calculations;

o) description of fire detection, actuation and control systems.

A.3 Specific details

A.3.1 Pre-engineered systems

For pre-engineered systems, the end-user shall be provided with the manufacturer's system design and maintenance information.

A.3.2 Engineered systems

For engineered systems, the end-user shall be provided with the manufacturer's system design and maintenance information.

Details of the system shall include the following:

1. information and calculations on the amount of extinguishant;

2. container storage pressure and extinguishant quantity;

3. capacity of the container;

4. the location, type and flow rate of each nozzle, including equivalent orifice area and pressure-reducing devices, if applicable;

5. the location, size and equivalent lengths or resistance coefficients of pipe fittings and hoses; pipe size reduction and orientation of tees shall be clearly indicated;

6. the location and size of the storage facility.

Information shall be submitted pertaining to the location and function of the detection devices, operating devices, auxiliary equipment and electrical circuitry, if used. Apparatus and devices shall be identified. Any special features shall be adequately explained. The version of the flow calculation program shall be identified on the computer calculation printout.Annex В
(normative)

Determination of flame-extinguishing concentration of gaseous
extinguishants by the cup burner method

This Annex specifies the minimum requirements for determining the flame-extinguishing concentration of a gaseous extinguishant in air for flammable liquids and gases, employing the cup burner apparatus.

Diffusion flames of fuels burning in a round reservoir (cup), centrally positioned in a coaxially flowing air stream, are extinguished by addition of a gaseous extinguishant to the air.

The cup burner apparatus for these measurements shall be arranged and constructed as in Figure B.1, with the dimensions shown; the tolerance for all dimensions shall be 5 % unless otherwise indicated.

Key

1. diffuser

2. air/extinguishant in

3. fuel in

4. grind inner surface of cup a 45° angle

Figure B.1 — Cup burner apparatus

B.3.2 Cup

The cup shall be round and shall be constructed of glass, quartz or steel. It shall have an outside diameter in the range of 28 mm to 31 mm, with a wall thickness of 1 mm to 2 mm. It shall have a 45° chamfer into the top edge of the cup. There shall be a means of measuring the temperature of the fuel inside the cup at a location 2 mm to 5 mm below the top of the cup. The cup shall be substantially similar in shape to the example shown in Figure B.1. A cup intended for use with gaseous fuels shall have means of attaining a uniform gas flow at the top of the cup (e.g. the cup may be packed with refractory materials).

The chimney shall be of round glass or quartz construction. It shall have an inside diameter of 85 mm ± 2 mm and a wall thickness of 2 mm to 5 mm, with a height of 535 mm ± 5 mm.

The diffuser shall have a means of fitting to the bottom end of the chimney. It shall have a means of admitting a premixed stream of air and extinguishant; and have a means of uniformly distributing the air/extinguishant flow across the cross-section of the chimney. The temperature of the air/extinguishant mixture within the diffuser shall be 25 °С ± 10 °С, measured with a calibrated temperature sensor.

A liquid fuel supply shall be capable of delivering liquid fuel to the cup while maintaining a fixed, but adjustable, liquid level therein.

A gaseous fuel supply shall be capable of delivering a fuel gas at a controlled and fixed rate to the cup.

A manifold shall receive air and extinguishant and deliver them as a single mixed stream to the diffuser.

A means for delivering air to the manifold shall allow adjustment of the air flow rate. It shall have a calibrated means of measuring the air flow rate.

A means for delivering extinguishant to the manifold shall allow adjustment of the extinguishant flow rate. If the method according to B.7.2 is used for the determination of the extinguishant concentration, there shall be a calibrated means of measuring the extinguishant flow rate.

The delivery system shall deliver a representative and measurable sample of the agent to the cup burner in gaseous form.

Air shall be clean, dry and oil-free. The oxygen concentration shall be a volume fraction of (20,9 ± 0,5) %. The source and the oxygen content of the air used shall be recorded.

NOTE "Air" supplied in commercial high-pressure cylinders may have an oxygen content significantly different from 20,9 %.

Fuel shall be of a certified type and quality.

The extinguishant shall be of certified type and meet the specifications of the supplier. Multi-component extinguishants should be provided premixed. Liquefied extinguishants shall be provided as pure extinguishant, i.e. not pressurized with nitrogen. Prior to commencing tests, the composition of the extinguishing gas shall be analysed.

The fuel temperature shall be preconditioned to 25 °С ± 3 °С or to 5 °С ± 3 °С above the open cup flash point, whichever is the higher. During this period, the liquid level in the cup shall be adjusted so that the fuel level is above the means for temperature measurement of the fuel.

NOTE The fuel temperature is meant to be the temperature at the start of the test.

NOTE On an initial run, it is convenient to use relatively large flow increments to ascertain the approximate extinguishant flow required for extinguishment, and on subsequent runs to start at a flow rate close to the critical and to increase the flow by small amounts until extinguishment is achieved.

NOTE On an initial run, it is convenient to employ relatively large flow increments to ascertain the approximate extinguishant flow required for extinguishment, and on subsequent runs to start at a flow rate close to the critical and to increase the flow by small amounts until extinguishment is achieved.

The preferred method for determining the concentration of extinguishant vapour in the extinguishant plus air mixture which just causes flame extinguishment is to use a gas-analysing device, calibrated for the concentration range of the extinguishant-air mixtures being measured. The device may have continuous sampling capability (e.g. on-line gas analyser) or may be of a type which analyses discrete samples (e g. gas chromatography). Continuous measurement techniques are preferred.

Alternatively, the remaining concentration of oxygen in the air/extinguishant mixture in the chimney below the cup can be measured with a continuous oxygen-analysis device. The oxygen concentration value is influenced by the extinguishant concentration. The extinguishant concentration is then calculated as follows:

C_£ = 100 1-М (B.1)

^cs)

where

c_E is the extinguishant concentration, as a volume fraction in percent;

c₀ is the oxygen concentration of the air/extinguishant mixture in the chimney, as a volume fraction

in percent;

c_s is the oxygen concentration in the supply air, as a volume fraction in percent.

The extinguishant concentration in the extinguishant plus air mixture may, alternatively, be calculated from the measured flow rates of the extinguishant and air. Where mass flow rate devices are employed, the resulting mass flow rates need to be converted to volumetric flow rates as follows:

V_l=m_llp_i (B.2)

where

V_i is the volumetric flow rate of gas /, in litres per minute;

m_t is the mass flow rate of gas /', in grams per minute;

p_t is the density of gas /, in grams per litre.

Care should be taken to use the actual vapour density. The vapour density of many halogenated hydrocarbons at ambient temperature and pressure may differ by several percent from that calculated by the ideal gas law.

EXAMPLE The density of HFC-227ea vapour at a pressure of 101,3 kPa and temperature of 295 К is approximately 2,4 % higher than would be calculated for an ideal gas. At a pressure of 6,7 kPa (6,6 %), however, the difference between the actual vapour density and that calculated for an ideal gas is less than 0,2 %.

Published property data should be used where possible. Estimating techniques may be used when published data are lacking. The source of physical property values used should be recorded in the test report.

The concentration of extinguishant as a volume fraction in percent, C, is calculated as follows:

C_E= ——хЮО (B.3)

Чаіг (text

where

c_E is the extinguishant concentration, as a volume fraction in percent;

<7air is the volumetric flow rate of the air, in litres per minute;

<?ext is the volumetric flow rate of the extinguishant, in litres per minute.

B.8 Reporting of results

The following information at least should be included in the report of results:

1. schematic diagram of apparatus, including dimensions and description of materials used;

2. source and assay of the extinguishant, fuel and air;

3. for each test, the fuel temperature at the start of the test, the fuel temperature at the time of extinguishment, and the temperature of the air/extinguishant mixture at extinguishment;

4. extinguishant, gaseous fuel and air flow rates at extinguishment; if method B.7.1 is used, the extinguishant concentration or the oxygen concentration instead of the extinguishant flow rate;

5. method used to determine the extinguishing concentration;

6. extinguishant concentration at extinguishment for each test;

7. measurement error analysis.

Annex C
(normative)

Fire extinguishment/area coverage fire test procedure for engineered
and pre-engineered extinguishing units

C.1 Requirements

C.1.1 An engineered or pre-engineered extinguishing system unit shall mix and distribute its extinguishant and shall totally flood the enclosure when tested in accordance with this test method under the maximum design limitations and most severe installation instructions. (See also C.1.2.)

C.1.2 When tested as described in C.4.1, C.4.2 and C.5.2 an extinguishing system unit shall extinguish all visible flaming within 30 s after the end of extinguishant discharge. When tested as described in C.5.1 an extinguishing system unit shall extinguish all visible flaming and prevent re-ignition of the fires after a 10 min soaking period (also measured from the end of extinguishant discharge). When tested as described in C.6.3 an extinguishing system unit shall “knock-down” the flames within 60 s after the end of extinguishant discharge (that means there are only flames allowed at the top edges of the 2 inner sheets) and extinguish all visible flaming within 3 min after the end of extinguishant discharge and also prevent re-ignition of the fires after a 10 min soaking period (also measured from the end of extinguishant discharge).

C.1.3 The tolerance applicable to dimensions specified in the description of test facilities shall be 5 %, if not otherwise stated.

C.2 Type of test

The tests described herein consider the intended use and limitations of the extinguishing system unit, with specific reference to:

1. the area coverage for each type of nozzle;

2. the operating temperature range of the system;

3. location of nozzles in the protected area;

4. either maximum length and size of piping and number of fittings to each nozzle, or minimum nozzle pressure;

5. maximum discharge time;

6. maximum fill density;

7. extinguishing concentrations for specific fuels.

The tests to be conducted are listed in Table C.1.

Table C1 — Tests to be conducted

C.3 Extinguishing system

C.3.1 For the extinguishing tests described in C.5.1 and C.5.2, the agent containers are to be conditioned to the minimum operating temperature specified in the manufacturer's installation instructions.

The extinguishing system shall be assembled as follows:

1. Pre-engineered-type extinguishing system unit - using its maximum piping limitations with respect to number of fittings and length of pipe to the discharge nozzles and nozzle configuration(s) as specified in the manufacturer’s design and installation instructions.

2. Engineered-type extinguishing system unit - using a piping arrangement that results in the minimum nozzle design pressure at 20 °С ± 2 °С.

C.3.2 For the extinguishing tests described in C.6.1, C.6.2 and C.6.3, the agent containers shall be conditioned at 20 °С ±2 °С for a minimum period of 16 h prior to conducting the test. In these tests the jet energy from the nozzles shall not influence the development of the fire.

C.3.3 For all tests, the extinguishing system shall be arranged and dimensioned with regard to the following:

For liquefied extinguishants the time for the discharge of the pre-liquid gas phase plus the two-phase flow shall be 8 s to 10 s. Non-superpressurized liquefied extinguishant discharge can be limited by cutting off with appropriate means positioned close to the nozzle, subject to the discharge being between 65 % to 90 % of the stored agent quantity.

For non-liquefied extinguishants the discharge time shall be 50 s to 60 s, limited by cutting off the discharge with appropriate means. For the tests, the amount of agent discharged in the test enclosure shall be between 65 % and 90 % of the stored agent quantity.

C.4 Extinguishing concentration

C.4.1 The extinguishing agent for tests C.5.1, C.5.2, C.6.1, C.6.2 and C.6.3 shall be 76,9 % (i.e. 100/safety factor, where the safety factor is 1,3 of the intended minimum design concentration specified in the manufacturer's design and installation instructions at the ambient temperature of 20 °С ± 2 °С within the enclosure. In the tests described in C.5.1 and C.5.2, the same extinguishing concentration has to be used as in the tests described in section C.6.2.

The quantity to reach the concentration within the enclosure can be established using the Equation (1) and Equation (2) (in 7.6.2 and 7.6.3) for liquefied gases and non-liquefied gases respectively.

C.4.2 A cold discharge test using the same quantity (± 2 %) of extinguishant is to be conducted to verify the actual concentration of extinguishant.

For liquefied extinguishants, the agent concentration shall be measured in the cold discharge test.

For non-liquefied extinguishants, the agent concentration or alternatively the oxygen concentration shall be measured. The extinguishant concentration is then calculated from the oxygen concentration using the following formula:

=

(C.1)

100 1- —-5-

l 120,95

where

c_E is the extinguishant concentration, as a volume fraction in percent;

c_a is the oxygen concentration measured in the test enclosure, as a volume fraction in percent.

C.5 Nozzle distribution verification tests

C.5.1 Nozzles minimum height/maximum area coverage test

C.5.1.1 Test facility

C.5.1.1.1 Construction

The test enclosure shall meet the following requirements:

1. the area, a*b (see Figure C.1), and height, H, of the enclosure shall correspond to the maximum nozzle area coverage and minimum nozzle height specified by the manufacturer;

2. a means of pressure relief shall be provided;

3. closable openings shall be provided directly above the test cans to allow for venting prior to system actuation;

4. one baffle is to be installed between the floor and ceiling with the height of the room. It is to be installed halfway between the nozzle location and the walls of the enclosure (see Figure C.1 for 360° nozzle and Figure C.2 for 180° nozzle). The baffle is to be perpendicular to the direction between nozzle location and walls of the enclosure (see Figures C.1 and C.2), and be 20 % of the length of the short wall of the enclosure.