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.