4.1 PrincipleThis test procedure tests the effectiveness of a
water-based fire-fighting system against a combination of a pool fire
and a cargo fire in two simulated freight trucks. At least two tests
should be conducted at the minimum and the maximum ceiling to nozzle
distance limitations, specified by the manufacturer.
4.2 Fire sourcesThe primary fire sources consist of:
- a flammable liquid pool fire;
- plastic commodity
cardboard cartons; and
- a non-fire retardant tarpaulin.
4.2.1 N-Heptane should be
used as the flammable liquid.
4.2.2 A cartoned plastic commodity should be used for the
cargo of the simulated freight trucks. An acceptable commodity is either
the EUR Std Plastic or the FMRC Std Plastic. These commodities consist
of empty polystyrene cups without lids, placed upside down, in
compartmented cartons. Details of the commodities are given in table
4.2.2.
Table 4.2.2 Details of specified plastic commoditiesDesignationNominal size of individual
carton (L x W x H) (mm)Number of cupsEUR Std Plastic
FMRC Std Plastic600 x 400 x 500
530 x 530 x 500120 125The corrugated cartons, partitions
and pads for packaging the cups should be non-fire retardant, have a "C"
flute configuration and be plain printed.
4.2.3 The tarpaulin used to cover the simulated
freight trucks should be made from non-fire retardant Polyester having a
nominal area weight of 600±50 g/m
2.
4.3 Apparatus4.3.1 Test areaThe tests should be conducted in a test hall as
specified in paragraph 3.4 under a flat, smooth, non-combustible ceiling
of at least 100 m . 2
4.3.2
Simulated freight trucksTwo simulated freight trucks should be constructed
using steel racks (see figures 4.3.2-1
through 3). The racks should have an overall length of 5.8 m, an
overall width of 2.4 m and be placed side by side, 0.6±0.05 m apart. The
overall height of the simulated freight trucks should be 4.5±0.05 m. At
1.2±0.05 m above the floor, a bottom should be built in each of the
racks. The bottom should be built of nominally 2 mm thick steel plates.
Horizontal steel beams on the sides facing the
flue space of the racks should be used to prevent the cartons from
falling over. The beams should be 0.08 ±0.02 m in height and be spaced
approximately 0.5 m vertically apart. The top beam should be positioned
at the level of the top of the stacks of cartons described in 4.3.3.
Around the bottom of the perimeter of the racks,
tailgates should be built. The tailgates should be 0.6 m high and be
constructed from nominally 12 mm thick non-combustible fibre boards.
Nominally 50 mm by 50 mm crossbeams should be
installed perpendicular to the long side, at the top of each of the two
racks. The crossbeams should be made from wood and spaced approximately
0.6 m apart.
The sides and the top of the two racks
should be fully covered with a tarpaulin as specified in paragraph
4.2.3. The tarpaulin should be stapled to the tailgates all around the
simulated freight trucks and to both ends of each of the nine wooden
crossbeams.
4.3.3 The cargo of
the simulated freight trucksThree stacks of cardboard cartons should be located on
each of the simulated freight trucks. The central stack should consist
of plastic commodity cardboard cartons, the outer two stacks should
consist of cardboard cartons without plastic cups (with internal
divisions only). All stacks should be placed on conventional wood
pallets. Spacers made of a suitable non-combustible material should be
used under the pallets to provide for a vertical distance between the
top of the stacks and the top of the simulated freight trucks of
0.5±0.05 m.
If the EUR Std Plastic
commodity cartons are used, each of the carton stacks should consist of
60 cartons, and have an overall dimension of 1.6 m by 1.8 m by 2.5 m
(height).
If the FMRC Std Plastic
commodity cartons are used, each of the carton stacks should consist of
45 cartons, and have an overall dimension of 1.6 m by 1.6 m by 2.5 m
(height).
All outer columns of
cartons should be stapled together at all rows to prevent the stacks
from falling over.
The distance
between the carton stacks and the flue space, as well as between the
individual carton stacks should be 0.3±0.05 m.
4.3.4 Target arraysTwo target arrays, with an overall length of 8.0 m,
made from the tarpaulin as specified in paragraph 4.2.3, should be
installed at the same overall height of the simulated freight trucks.
The tarpaulin should be attached, using staples, to a wood framework so
that a 1 m wide horizontal and a 3.3 m high vertical area is formed.
Behind each of the target tarpaulins should be a single row of empty
cardboard cartons as defined in paragraph 4.2.2, which are located
continuously along the target array. The cardboard cartons should be
supported along their bottom as well as along their outside surfaces to
prevent them from falling over during the fire test. See figures 4.3.2-2, 4.3.2-3 and 4.3.4.
4.3.5 Pool fire trayA nominally 2 m long by 1.5 m wide by 2 mm thick steel
tray should be positioned centrically under the simulated freight trucks
as shown in figure 4.3.2-3. The
tray should have a 100 mm rim height. Means should be provided to
prevent overflowing of the tray.
4.4 Nozzle positioningNozzles should be installed in an array above the
simulated freight trucks in accordance with the manufacturer's design
and installation criteria. However, nozzles along the centreline between
the simulated freight trucks are not permitted to be installed closer to
the centre point of the pool fire tray than half the nozzle spacing.
4.5 InstrumentationInstrumentation for the continuous measuring and
recording of test conditions should be employed.
The
following measurements should be made:
- The temperature
flush with the ceiling at three positions. See figure 5.
- The temperature at
0.08±0.02 m underneath the bottom of the simulated freight
trucks, at two positions. See figure 4.5.
- System water pressure near the
centre of the piping array.
- The total water flow rate
of the system.
Note: Additional ceiling temperature
measurement positions should be used if it is suspected that other
positions are being exposed to higher temperatures.
4.6 Test programme and test procedure4.6.1 Test programmeTests should be conducted at the minimum system water
pressure, minimum and maximum ceiling heights as well as at the minimum
and maximum distance between the lowest part of the nozzles and the
ceiling, as specified by the manufacturer. The minimum ceiling height
should not to be less than 4.8 m.
4.6.2 Test procedureThe test procedure should be applied as follows:
- 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.
- The tray should be filled with 10 mm (30 L)
of n-Heptane on a 10 mm water base.
- The measurements
are started.
- The flammable liquid pool fire should be
lit by means of a torch or a match.
- The fire should be
allowed to burn for a period of 10 minutes or until is it clear
that any of the acceptance criteria has failed.
- Any
remaining fire should be manually extinguished.
- The
test is terminated.
4.7 Acceptance criteriaThe following three criteria should be met:
- The temperature measured underneath the simulated
freight trucks at either measurement position should be reduced
to below 500°C no later than three minutes after ignition and to
below 300°C no later than four minutes after ignition.
- The cardboard cartons in the target arrays should not
ignite.
- The maximum five minute average ceiling surface
temperature at any measurement position should not exceed 600°C.