2 GENERAL REQUIREMENTS
2.1 Sampling
The nozzles and other components to be tested should be supplied by the
manufacturer together with design and installation criteria, operational
instructions, drawings and technical data sufficient for the identification of the
components.
2.2 Tolerances
Unless otherwise stated, the following tolerances should apply:
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.1 length: ± 2% of value;
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.2 volume: ± 5% of value;
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.3 pressure: ± 3% of value; and
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.4 temperature: ± 2% of value.
2.3 Observations
The following observations should be made during and after each test:
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.1 time of ignition;
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.2 activation time of first nozzle;
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.3 time when water flows out through first nozzle;
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.4 time when water flow is shut off;
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.5 time when the test is terminated; and
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.6 total number of activated nozzles.
2.4 Test hall and environmental conditions
The test hall where the tests are conducted should have a minimum floor
area of 300 m2 and a ceiling height in excess of 8 m. The test hall may
be equipped with a forced ventilation system, or be natural ventilated, in order to
ensure that there is no restriction in air supply to the test fires. The test hall
should have an ambient temperature of between 10 and 25oC at the start of
each test.
2.5 Measurement equipment
2.5.1 Temperatures should be measured using plain K-type thermocouple
wires not exceeding 0.5 mm in diameter. The thermocouple head should be protected
against direct water impingement, e.g. by tin cans.
2.5.2 System water pressure should be measured by using suitable
equipment. Total water flow rate should be determined by a direct measurement or
indirectly by using the pressure data and "k" factor of the nozzles.
2.5.3 The measurements should be made continuously throughout the tests.
2.6 System operational conditions
The tests should simulate the conditions of an actual installed system
regarding objectives such as time delays between the activation of the system and
minimum system water pressure or water delivery. In addition, the use of a
pre-primed fire suppression enhancing additive, if applicable, should be taken into
account.
3 DETERMINATION OF FIRE SUPPRESSION AND CONTROL CAPABILITIES
3.1 Principle
These test procedures test the effectiveness of a water-based
fire-fighting system against two different scenarios: a cargo fire in a simulated
freight truck, and a passenger vehicle fire.
3.2 Fire source
3.2.1 The primary fire source for both scenarios consists of EUR standard
wood pallets (ISO 6780:2003), stored inside with the moisture content of 14 ± 2%.
Figure 3.2.1 shows details of a EUR pallet.
3.2.2 Plywood panels made of pine or spruce are used as targets. The
panels should be approximately 12 mm thick. The ignition time of the panel should
not be more than 35 s and the flame spread time at 350 mm position should not be
more than 100 s as measured in accordance with resolution A.653(16).
3.2.3 For ignition, commercial heptane should be applied.
Figure 3.2.1 - Typical dimensions of the standard EUR pallet
3.3 Apparatus
3.3.1 Test area
The tests should be conducted in a test hall as specified in paragraph 2.4 above,
under a flat, smooth, non-combustible ceiling of at least 100 m2. There
should be at least a 1 m space between the perimeters of the ceiling and any wall of
the test hall.
3.3.2 Fire scenario 1: cargo fire in a simulated freight
truck (see figures 3.3.2.1 to 3.3.2.3)
3.3.2.1 The primary fuel package consists of 112 wood pallets arranged in an array of
2 (wide) x 7 (high) x 8 (long) and raised up on a level of 2.8 m so that the top
level of the fuel package is at 3.8 to 3.9 m above the floor.
3.3.2.2 The support frame for the wood pallet array of paragraph 3.3.2.1 should be
constructed using open steel racks. The wood pallet piles should be standing freely
on horizontal steel beams without any solid bottoms.
3.3.2.3 The fuel pallet array should be half-shielded by a 4.5 m long, 2.6 m wide
steel plate (thickness at least 2 mm) at 4 m height. The plate should be properly
fixed so that during a test it does not bend to provide an unobstructed passage of
water onto the fuel package.
3.3.2.4 Plywood panel targets (acting also as obstructions) of dimensions 3.6 m
(wide) x 2.4 m (high) should be arranged symmetrically on both sides of the fuel
package at 1 m distance so that the top edge is at the same level as the top level
of the wood pallet array.
3.3.2.5 The fire should be ignited by two steel trays centrally located
under the fuel package as shown in figures 3.3.2.1 to 3.3.2.3. The square trays are
25 cm high and 0.1 m2 of free surface area. The trays should be filled
with water and 1 l of heptane so that the free rim height above the liquid
surface is 4 cm. The distance between the bottom of the wood pallet piles and liquid
surface is 29 cm.
Figure 3.3.2.1 - Side view of the cargo fuel package in a simulated truck
Figure 3.3.2.2 - End view of the cargo fuel package in a simulated truck
Figure 3.3.2.3 - Top view of the cargo fuel package in a simulated truck
3.3.3 Fire scenario 2: passenger vehicle fire (see figures 3.3.3.1 and
3.3.3.2)
3.3.3.1 The primary fuel package consists of 12 wood pallets arranged in an array of
1 pallet (wide) x 6 pallets (high) x 2 pallets (long) constructed inside a passenger
vehicle mock-up.
3.3.3.2 The passenger vehicle mock-up is constructed of nominally 2 mm steel.
3.3.3.3 Plywood panel targets (acting also as obstructions) of dimensions 1.2 m
(wide) x 1.75 m (high) should be arranged symmetrically on both sides of the mock-up
at 0.6 m distance so that the top edge is at the same level as the top level of the
mock-up car.
3.3.3.4 The fire should be ignited by a steel tray centrally located
under the fuel package as shown in figures 3.3.3.1 and 3.3.3.2. The square tray is
10 cm high and 0.1 m2 of free surface area. The tray should be filled
with water and 1 l of heptane so that the free rim height above the liquid
surface is 4 cm.
3.4 Nozzle positioning
Nozzles should be installed in an array at the ceiling level in accordance with the
manufacturer's design and installation criteria. Tests should be repeated with three
different relative locations between the nozzle array and the fuel package, i.e.
centre of ignition under one nozzle, between two nozzles and between four nozzles,
as shown in figure 3.4.
Figure 3.3.3.1 - Side view of the passenger vehicle fuel package
(The dashed lines visualize the shape of a car; the ceiling plate is to be fixed in
its location as found most practical)
Figure 3.3.3.2 - Top view of the passenger vehicle fuel package
Figure 3.4 - Nozzle positioning in the two scenarios
3.5 Instrumentation
3.5.1 Instrumentation for the continuous measuring and recording of test conditions
should be employed. At least the following measurements should be made:
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.1 gas temperature at 7.5 cm below the ceiling at locations shown in
figure 3.5.1;
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.2 gas temperature at the targets to indicate ignition of targets as
shown in figure 3.5.2; and
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.3 system water pressure near the centre of the piping array.
3.5.2 System water flow rate should be defined with suitable means for the
system.
Figure 3.5.1 - Thermocouple locations in the two scenariosfootnote
Figure 3.5.2 - Thermocouple locations at the plywood targets for determining
ignition of targetsfootnote
3.6 Test programme and test procedure
3.6.1 Test programme
3.6.1.1 Tests should be conducted at the minimum system water pressure at the minimum
distance between the lowest part of the nozzles and the ceiling, as specified by the
manufacturer.
3.6.1.2 Three tests should be conducted at ceiling heights 5 m and/or 2.5 m, with
different nozzle grid locations relative to the fuel package as specified in figure
3.4.1.
3.6.2 Test procedure
3.6.2.1 Prior to starting the test the moisture content of the fuel package should be
measured at several locations along the full package with a probe-type moisture
meter and the results should be reported.
3.6.2.2 The actual test procedure for all tests is as follows:
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.1 the water pressure used at the start of the test should be set at the
minimum value for the system specified by the manufacturer, flowing six
open nozzles. If more than six nozzles operate during the test, the
water supply pressure should be adjusted accordingly, to keep the
required minimum system water pressure;
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.2 the tray should be filled with 1 litre of heptane on the water base as
described in paragraph 3.3.2.5 or 3.3.3.4;
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.3 the measurements are started;
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.4 the flammable liquid pool fire(s) should be lit by means of a torch or
a match;
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.5 the fire should be allowed to burn freely for a period of 2.5
min;footnote
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.6 the test is continued for 30 min after system activation;
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.7 any remaining fire should be manually extinguished; and
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.8 the test is terminated.
3.7 Acceptance criteria
The principal acceptance criteria are based on the following factors:
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.1 gas temperatures measured at locations not directly affected by
impinging flames;
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.2 damage to the fuel package; and/or
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.3 ignition of targets.
Note 1: Damage to the fuel package is defined by the fraction of
charring of the full package. The damage to each individual wood pallet
should be evaluated separately and the total fraction calculated based
on the detailed results. Totally black, i.e. totally charred pallet is
denoted as 100% damage of the pallet (even though the pallet may have
maintained its shape) and totally intact pallet is denoted as 0% damage.
Partially charred pallets should be visually evaluated. Proper and
adequate photographs of the damaged fuel package should be included in
the test report.
Note 2: Ignition of targets is defined by the method described in
figure 3.5.2, if the visibility during the test is such that it cannot
be visually observed.
3.7.1 Fire scenario 1: cargo fire in a simulated freight truck (ceiling height
5 m)
The following four criteria should be met:
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.1 after system activation the maximum five minute average at any of the
three measurement locations at the exposed end of the fuel package
should not exceed 300oC;
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.2 after system activation the maximum five minute average at any of the
three measurement locations at the concealed end of the fuel package
should not exceed 350oC;
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.3 total damage to the wood pallet array should not exceed 45% as defined
after the test; and
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.4 the plywood targets should not ignite during the test.
3.7.2 Fire scenario 2: passenger vehicle fire
The following two criteria should be met: