4 Method of Test

4.1 Principle

This test procedure enables the determination of the effectiveness of different water-based extinguishing systems against spray fires, cascade fires, pool fires and class A fires which are obstructed by an engine mock-up.

4.2 Apparatus

4.2.1 Engine Mock-Up

The fire test should be performed in a test apparatus consisting of:

.1 An engine mock-up of size (width x length x height) 1 m x 3 m x 3 m constructed of sheet steel with a minimal thickness of 5 mm. The mock-up is fitted with two steel tubes diameter 0.3 m and 3 m length that simulate exhaust manifolds and a grating. At the top of the mock-up a 3 m² tray is arranged. See Figure 2.
.2 A floor plate system 4 m x 6 m x 0.5 m high surrounding the mock-up with three trays, 2, 2, and 4 m², equalling a total area of 8 m², underneath. See Figure 2.

4.2.2 Test Room

.1 Class 1-Engine rooms

The test should be performed in 100 m² room with 5 m ceiling height and ventilation through a 2 m x 2 m door opening. Fires and engine mock-up according to tables 2, 3 and Figure 1.

.2 Class 2 - Engine-room.

The tests should be performed in a room having a specified area greater than 100 m², specified height of from 5 to 7.5 m and ventilation through a 2 m x 2 m door opening, up to a total volume for the room of 3,000 m³. Fires and engine mock-up should be according to tables 2 and 3 and figure 1.

.3 Class 3 - Engine-room

The test should be performed in a fire test hall with a minimum floor area of 300 m², and a ceiling height in excess of 10 m and without any restrictions in air supply for the test fires. Fires and engine mock-up should be according to tables 2 and 3 and figure 1."

Figure 1 Test Room Layout

Table 2 Test Programme

Test No.	Fire Scenario	Test Fuel
1	Low pressure horizontal spray on top of simulated engine between agent nozzles	Commercial fuel oil or light diesel oil
2	Low pressure spray on top of simulated engine centred with nozzle angled upward at a 45º angle to strike a 12–15 mm diameter rod 1 metre away.	Commercial fuel oil or light diesel oil
3	Low pressure concealed horizontal spray fire on side of simulated engine with oil spray nozzle positioned 0.1 m from the end of the engine.	Commercial fuel oil or light diesel oil
4	Combination of worst spray fire from Tests 1–3 and fires in trays under (4 m²) and on top of the simulated engine (3 m²)	Commercial fuel oil or light diesel oil
5	High pressure horizontal spray fire on top of the simulated engine	Commercial fuel oil or light diesel oil
6	Low pressure low flow concealed horizontal spray fire on the side of the simulated engine with oil spray nozzle positioned 0.1 m in from the end of the engine and 0.1 m² tray positioned 1.4 m in from the engine end at the inside of the floor plate	Commercial fuel oil or light diesel oil
7	0.5 m² central under mock-up	Heptane
8	0.5 m² central under mock-up	SAE 10W30 mineral based lubrication oil
9	0.5 m² on top of bilge plate centred under exhaust plate	Heptane
10	Flowing fire 0.25 kg/s from top of mock up. See figure 3	Heptane
11	Class A fires wood crib (see Note) in 2 m² pool fire with 30 sec preburn. The test tray should be positioned 0.75 m above the floor as shown in figure 2	Heptane
12	A steel plate (20 cm x 60 cm x 5 cm) offset 20º to the spray is heated to 350ºC by the top low pressure, low flow spray nozzle positioned horizontally 0.5 m from the front edge of the plate. When the plate reaches 350ºC, the system is activated. Following system shut off, no reignition of the spray is permitted.	Heptane
13	4 m² tray under mock-up	Commercial fuel oil or light diesel oil
Note 1 The wood crib is to weigh 5.4 to 5.9 kg and is to be dimensioned approximately 305 by 305 by 305 mm. The crib is to consist of eight alternate layers of four trade size 38.1 by 38.1 mm kiln-dried spruce or fir lumber 305 mm long. The alternate layers of the lumber are to be placed at right angles to the adjacent layers. The individual wood members in each layer are to be evenly spaced along the length of the previous layer of wood members and stapled. Following the conditioning, the moisture content of the crib is to be measured with a probe type moisture meter. The moisture content of the crib should not exceed 5% prior to the fire test. Note 2 Tests 4, 7, 8 and 13 are not required for bilges with a separate fire protection system and are not applicable to bilges with a depth of more than 0.75 m (see section 4.3).

Table 3 Oil Spray Fire Test Parameters

Category A Engine - Room Class 1 - 3
Fire type	Low pressure	Low pressure, low flow	High pressure
Spray nozzle	Wide spray angle (120 to 125 º) full cone type	Wide spray angle (80 º) full cone type	Standard angle (at 6 Bar) full cone type
Nominal oil pressure	8 Bar	8.5 Bar	150 Bar
Oil flow	0.16 ± 0.01 kg/s	0.03 ± 0.005 kg/s	0.050 ± 0.002 kg/s
Oil temperature	20 ± 5 ºC	20 ± 5 ºC	20 ± 5 ºC
Nominal heat release rate	5.8 ± 0.6 MW	1.1 ± 0.1 MW	1.8 ± 0.2 MW

Figure 2 Engine Mock-up Test Apparutus

Figure 3 Flowing Fire from Top of Mock-up

4.3 Extinguishing System

The extinguishing system should be installed according to the manufacturer's design and installation instructions. For class 3 engine-rooms, the maximum vertical distance between levels of nozzles should be limited to 7.5 m and the lowest level of nozzles should be at a minimum height of 5 m above the floor. For actual installation with bilges more than 0.75 m in depth, nozzles must be installed in the bilges in accordance with manufacturer's recommendations as developed from representative fire tests.

4.4 Procedure

4.4.1 Ignition

The tray/s used in the test should be filled with at least 50 mm fuel on a water base. Freeboard is to be 150 ± 10 mm.

4.4.2 Flow and Pressure Measurements (Oil System)

The oil flow and pressure in the oil system should be measured before each test. The oil pressure should be measure during the test.

4.4.3 Flow and Pressure Measurements (Extinguishing System)

Agent flow and pressure in the extinguishing system should be measured continuously on the high pressure side of a pump or equivalent equipment at intervals not exceeding 5 seconds during the test, alternatively, the flow can be determined by the pressure and the K factor of the nozzles.

4.4.4 Duration of Test

After ignition of all fuel sources, a 2 minute preburn time is required before the extinguishing agent is discharged for the oil tray fires and 5-15 seconds for the oil spray and heptane fires and 30 seconds for the class A fire test (test No.11)

Extinguishing agent should be discharged for 50% of the discharge time recommended by the manufacturer or 15 minutes whatever is less. The oil spray, if used, should be shut off 15 seconds after the end of agent discharge.

4.4.5 Observations Before and During the Test

Before the test, the test room, fuel and mock-up temperature is to be measured.

During the test the following observations should be recorded:

.1 the start of the ignition procedure;
.2 the start of the test (ignition);
.3 the time when the extinguishing system is activated;
.4 the time when the fire is extinguished, if it is;
.5 the time when the fire extinguishing system is shut off;
.6 the time of reignition. if any;
.7 the time when the oil flow for the spray fire is shut off; and
.8 the time when the test is finished.

4.4.6 Observations After the Test

.1 Damage to any system components;
.2 The level of oil in the tray(s) to make sure that no limitation of fuel occurred during the test.
.3 Test room, fuel and mock-up temperature.