---

If one of the first two tests is not successful repeat that test. If this repeat test is successful carry out a second repeat test; otherwise terminate the test series. The concentrate conforms to Clause 10 if three tests are successful.

H.1.2 Temperature and wind speed

NOTE If necessary some form of wind-screen can be used.

H.1.3 Records

During the fire test record the following:

1. location;

2. air temperature;

3. fuel temperature;

4. water temperature;

5. foam solution temperature;

6. wind speed;

7. 90 % control time;

8. 99 % control time;

9. extinction time;

10. 25 % burn-back time.

NOTE 90 % control time and burn-back time can be determined either visually by an experienced person or from thermal radiation measurements. Annex J gives details of a method suitable for low expansion foams.

H.1.4 Foam solution

Prepare a foam solution following the recommendations from the supplier for concentration, maximum premix time, compatibility with the test equipment, avoiding contamination by other types of foam, etc.

Use potable water to prepare the foam solution and, if the supplier claims that the concentrate is suitable for use in sea water make a second foam solution at the same concentration using the simulated sea water in accordance with G.4.

H.1.5 Fuel

Use an aliphatic hydrocarbon mixture having physical properties according to the following specification:

1. distillation range: 84 °С to 105 °С;

2. maximum difference between initial and final boiling points: 10 °С;

3. maximum aromatic content: a mass fraction of 1 %;

4. density at 15 °С: (700 ± 20) kg/m³.

NOTE 1 The normal value of surface tension of the aliphatic hydrocarbon mixture measured in accordance with F.2.1 is 21 mN m'¹ to 22 mN m'¹.

NOTE 2 Typical fuels meeting this specification are certain solvent fractions sometimes referred to as commercial heptane.

H.2 Gentle application fire test

H.2.1 Apparatus

H.2.1.1 General

Circular fire tray of stainless steel grade EN: X5CrNi18-10 with dimensions as follows:

1. internal diameter at rim (2400 ± 25) mm;

2. depth (200 + 15) mm;

3. nominal thickness of steel wall 2,5 mm,

and with a vertical stainless steel backboard (1 ± 0,05) m high and (1 + 0,05) m long and 2,5 mm thick fitted as closely as possible along the top of the tray wall, or formed by an extension of the tray wall.

NOTE The tray has an area of approximately 4,52 m².

H.2.1.2 Foam making equipment, as described in G.1.3.

H.2.1.3 Stainless steel burn-back pot, of nominal thickness 2,5 mm, diameter (300 ± 5) mm and height (250 ± 5) mm.

H.2.2 Test procedure

Place the tray directly on the ground and ensure that it is level. Set up the foam nozzle horizontally, (1 ± 0,05) m above the fuel level in a position where the central part of the foam discharge will strike the centre axis of the backboard (0,5 ± 0,1) m above the fuel level (see Figure H.1). Clean the tray. Add approximately 90 I of water and check that the base is completely covered. Add (144 ± 5) I of fuel, to give approximately 150 mm between the fuel surface and the top of the tray wall.

Ignite the fuel, not less than 3 min and not more than 5 min after adding it. Start foam application (60 + 2) s after full involvement. Readjust the nozzle to ensure that the jet continues to hit the centre of the backboard. Apply foam for (300 ± 2) s. Record the extinction time as the period between the start of foam application and extinction.

NOTE 1 Foams which have achieved burn-back resistance level A at extinguishing performance class I or II on the forceful application test need not be tested using gentle application.

NOTE 2 Extinction is not required for foams which have successfully extinguished the forceful application test of H.3 without achieving burn-back resistance level A.

NOTE 3 Foams which do not extinguish the gentle application test of H.2 can have a reduced burn-back resistance level because of flames remaining after foam application.

If the fire is not extinguished within (300 + 2) s and the foam has not achieved extinguishing performance class I or II terminate the test.

After a further (300 ± 10) s place the burn-back pot, containing (2 ± 0,1) I of fuel in the centre of the tray and ignite. Record the 25 % burn-back time.

Dimensions in metres

Key

1. backboard (non integral type shown)

2. foam-making nozzle

3. fuel

4. water

5. tray

Figure H.1 — Test fire arrangement for gentle application

H.3 Forceful application fire test

H.3.1 Apparatus

As for H.2.1 except that the tray does not have a backboard.

H.3.2 Procedure

Set up the tray and nozzle generally in accordance with H.2.2 but position the nozzle so that the central part of the foam discharge will fall directly on the fuel surface at a point (1 ± 0,1) m from the edge of the tray furthest from the nozzle (see Figure H.2).

Ignite the fuel not more than 300 s after adding it and allow to burn for (60 + 2) s after full involvement of the surface of the fuel. Apply foam for (180 ± 2) s and if the fire is extinguished record the extinction time as the instant when all flames have disappeared.

Stop applying foam and if the fire is not extinguished wait to see if any remaining flickers of flame are extinguished and record the extinction time.

(300 ± 10) s after stopping foam application place the burn-back pot containing (2 ± 0,1) I of fuel in the centre of the tray and ignite. Visually estimate when 25 % of the tray is covered by sustained flames or by "flare up" flames (See NOTE), ignoring any faint, barely visible, or transient flames: record the time elapsed since ignition of the burn-back pot as the 25 % burn-back time.

NOTE During the burn-back test a "flare up” can occur, in which large flames can be sustained for periods typically from 30 s to 3 min before decreasing in intensity.

Dimensions in metres

Key

1 water

2 fuel

3. foam making nozzle

4. tray

Figure H.2 — Test fire arrangement for forceful application

Annex I
(informative)

Small scale fire test

NOTE Annex H describes large scale fire tests for type approval. This annex describes a small scale fire test which can be suitable for quality control purposes.

1. internal diameter at rim (565 ± 5) mm;

2. height of vertical wall (150 ± 5) mm;

3. height of conical base (30 + 5) mm;

4. thickness of vertical wall (1,2 ± 0,2) mm,

with a turned over rim, and a drain point with valve at the centre of the conical base.

NOTE The tray has an area of approximately 0,25 m².

The fire tray is supported approximately 1 m above the ground on a steel frame with four legs. The tray is normally placed beneath a suitable fume extraction hood which will extract the smoke without interfering with the fire.

1. internal diameter at rim (120 ±2) mm;

2. internal depth (80 ± 2) mm;

3. thickness of wall (1,2 ± 0,2) mm,

with a turned over rim, and fitted with four studs at the base to give an overall height of (96 ± 2) mm. A chain fitted to the rim allows the burn-back pot to be lifted using a metal rod.

An aliphatic hydrocarbon mixture as specified in H.1.5.

Carry out the test under the following conditions:

1. air temperature (15 ± 5) °С;

2. fuel temperature (17,5 + 2,5) °С;

3. foam solution temperature (17,5 ± 2,5) °С.

Position the foam nozzle horizontally with the by-pass holes in the adjustable collar facing downwards at a height of (150 ± 5) mm above the rim of the fire tray (see Figure 1.2).

Prepare the foam solution following the recommendations of the supplier for concentration, maximum premix time, compatibility with test equipment, avoiding contamination by other types of foam, etc.

Set the nozzle pressure to 7 bar and the foam flow rate to (0,75 ± 0,025) kg/min by adjusting the collar and, if necessary, reducing the nozzle pressure. It is convenient to collect the foam in a tared vessel for 6 s and to weigh it to calculate the flow rate.

Position the nozzle while keeping it horizontal so that the foam strikes the centre of the fire tray. Shut off the foam discharge. Clean the tray and close the drain valve.

Place (9 ± 0,1) I of fuel in the tray, and (0,3 ± 0,01) I of fuel in the burn-back pot.

(120 ± 2) s after fuelling ignite the fuel and allow to burn for (60 + 2) s before starting foam application. Apply foam for (120 ± 2) s to the centre of the tray and record the times from the start of foam application to 90 % control, 99 % control, and complete extinction.

At the end of foam application ignite the fuel in the burn-back pot, and (60 + 2) s after the end of foam application lower the pot into the centre of the tray with a metal rod, taking care not to allow foam to enter the pot. Record the time taken from positioning of the burn-back pot to permanent full reinvolvement of the fire tray surface in flames as the burn-back time

.

Dimensions in millimetres

Key

1. burn-back pot

2. foam nozzle

3. backboard (optional)

4. adjustable boss

5. fire tray

6. foam solution

Figure 1.1 — Small scale fire test

Key

1. nozzle with foam diverter (see Figure I.3)

2. coupling (see Figure 1.4)

3. mixing tube (see Figure 1.5)

4. stabilizing tube (see Figure 1.6)

5. venturi (see Figure 1.7)

6. orifice plate G (see Figure 1.8)

7. spacing piece (see Figure 1.9)

8. orifice plate P (see Figure 1.10)

9. inlet (see Figure 1.11)

Figure I.2 — Foam making nozzle for small scale fire test

Dimensions in millimetres

40

20 і 20

* Г

. ' . ^0М6

022 ±0,05

Key

1 - 3 holes 0 H

2- knurled

З-16 threads

Figure I.3 — Sleeve and item 1 - Nozzle with foam diverter

Dimensions in millimetres

Key

1 - coarse knurled

50

1

13

31 x 45

1 x 45

NOTE End faces to be at 90° to axis

Dimensions in millimetres

Thread: Whitworth, 16 tpi

Chamfer each end 1 x 45°

Figure 1.6 — Item 4 - Stabilizing tube

Dimensions in millimetres

A

Key

1 4 holes 0 6 at 90 in same plane

Figure I.7 — Item 5 Venturi

Dimensions in millimetres

Key

1 slight radius

Faces parallel to within 0,02

Hole concentric with O.D. to within 0,02

Hole at 90° to each face within 0,01

Dimensions in millimetres

Bore and counter bore concentric to O.D. within 0,02

Counter bore face parallel to end face within 0,02

Counter bore faces and end faces square with axis to within 0,01

Chamfer thread edges 1 x 45°, leave other edges sharp

Dimensions in millimetres

Key

1 slight radius

Faces parallel to within 0,02

Hole concentric with O.D. to within 0,02

Hole at 90° to each face within 0,01

Dimensions in millimetres

Figure 1.10 — Item 8 - Orifice plate P

Bore and counter bore concentric to O.D. within 0,02

Figure 1.11 Item 9 - Inlet

Annex J
(informative)

Description of a radiation measurement method

J.1 Evaluation

Radiation measurement is a convenient and objective way to monitor the performance of a foam during the fire performance test. It reduces the need for visual observations (except for flame flickers and time for complete extinction).

This annex describes the equipment and procedure²) which have been used in a series of tests at one testing laboratory, and the methods used to interpret and present the results. The method is suitable for low and medium expansion foams but not for high expansion foams.

J.2 General arrangement of test

Place two radiometers diametrically in relation to the tray as shown in Figure J.1. The distance between the radiometers and the rim of the tray should be not less than twice the diameter of the tray and the height above the rim not less than 1,5 m.

NOTE Maximum distance is limited by the sensitivity of the radiometers.

Record the radiation levels continuously or with intervals not exceeding 1 s.

Dimensions in metres

Key

R - radiometers

1 - circular fire tray

Figure J.1 — Location of the radiometers for recording of the heat radiation during fire
performance tests

J.3 Technical data for radiometers³)

Use two radiometers of the Gordon or Schmidt-Boelter type. The meters should be water cooled. The temperature of the cooling water should be (30 ± 10) °С, and held constant during the measurements.

The radiometers should absorb at least 90 % of the incoming radiation within the range of wavelengths 0,6 pm to 15,0 pm.

For a fully developed fire the radiometer reading should be not less than 0,6 times full scale.

The radiometers should have a maximum non-linearity of ± 3 % of the nominal range of measurement, and a maximum response time of 2 s (up to 63 % of full response).

NOTE A radiometer with protective glass can be used, provided that the requirements on spectral sensitivity are satisfied. If it is assumed to be desirable, the recommendation to use the range of measurement as above can be changed, if the radiometers have a better linearity. Less than 40 % utilization is not advisable as the influence of background radiation might cause too high an effect.

J.4 Procedure

Correct the output from the two radiometers by deducting the background radiation recorded from 5 s to 10 s after the point of time for complete extinction.

Determine the mean value of the output from the two radiometers.

Determine the average radiation value (free burning radiation value) by averaging the recorded values over the 25 s period starting from the 30 s to the 5 s before start of the foam application (see Figure J.2).

Determine the relative radiation by dividing the output radiation from the radiometers with the calculated average free burning radiation value.

Instantaneous radiation values are subject to random fluctuations. Plot radiation values averaged over the period ± 5 s for each time value to produce a smoother curve, which facilitates interpretation.

The adjusted relative radiation is shown for the extinguishing test in Figure J.3 and for the burn-back test in Figure J.4; 90 % control is equivalent to the relative radiation 0,1.

The description above implies that computer controlled measuring practice is applied.

Key

X-axis duration time, min

Y-axis radiation, kW/m²

NOTE Foam application starts at 1 min, stops at 5 min. Burn-back test starts at 15 min.

Figure J.2 — Typical absolute radiation levels throughout a test

Key

X-axis time, min

Y-axis relative radiation, dimensionless

NOTE Foam application starts at 0 min, stops at 4 min; 90 % control is achieved at about 1 min 8 s.

Figure J.3 — Typical relative radiation levels throughout a test

Key

X-axis time, min

Y-axis relative radiation, dimensionless

NOTE Burn-back starts at 0 min.

Figure J.4 — Typical relative radiation levels during burn-back

Annex К
(informative)

A-Deviations

А-deviation: National deviation due to regulations, the alteration of which is for the time being outside the competence of the CEN/CENELEC member.

In the relevant CEN/CENELEC countries these А-deviations are valid instead of the provisions of the European Standard until they have been removed.

Denmark

Germany