Ventilation Performance Test of Inflatable Liferafts – New Requirements

Introduction

Refer to the latest revision of MSC.1/Circ. 1630/Rev.1, the tests required to obtain the type approval certificate of inflatable liferafts are as follows:

1. Visual Inspection
2. Drop Test
3. Jump Test
4. Weight Test
5. Towing Test
6. Mooring Out Test
7. Life raft Painter System Test
8. Weak Link Strength Test
9. Loading & Seating Test
10. Boarding Test
11. Closing Arrangement Test
12. Stability Test
13. Maneuverability test
14. Swamp Test
15. Canopy Closure Test
16. Buoyancy of Float-Free Life Raft Test
17. Damage Test
18. Righting Test
19. Inflation Test
20. Pressure Test
21. Detailed Inspection
22. Lifting Components Strength Test
23. Impact Test
24. Davit Launched Liferaft Boarding Test
25. Davit Launched Liferaft Strength Test
26. Cold Overload Test
27. Lowering Abrasion Test
28. Self-righting Test (self-righting liferaft only)
29. Submergence test (self-righting liferaft only)
30. Wind Velocity Test
31. Self-draining test (self-righting liferaft only)
32. Seam Strength Test

Recently, at the latest meeting of the IMO maritime safety committee (MSC 106), a new test called the “Ventilation Performance Test” was approved. The new test procedure will circulate after adoption at the next MSC meeting.

We at Marine Topics have collected a summary of what must perform to obtain type approval certificates for inflatable liferafts, besides the previous tests mentioned above. Stay with us.

Ventilation performance test

The details of the mentioned tests have been described in three parts:

1. Test Procedure
2. Acceptance Criteria
3. Significant Test Data

Test Procedure

Ventilation performance should be measured using the ventilation rate or CO2 concentration, as follows.

Ventilation rate method:

The ventilation rate should be measured under moored conditions. The test should be carried out with only the persons necessary on board to perform the test. All entrances should be kept closed. Ventilation openings should stay open.

CO2 concentration method:

The liferaft should be moored outdoors in ambient air with all entrances closed, and any ventilation openings remaining fully open. The average wind speed of the test environment during the test period should measure no greater than force 2 on the Beaufort scale.

To simulate the volume of persons inside the liferaft, the liferaft should be loaded with forms to represent the number of persons which the liferaft is permitted to accommodate, which provides a volume displacement equal to a body volume of 75 L per person. The forms should be evenly distributed on the surface of the floor of the liferaft.

If a heat source to simulate body heat is provided, it should be arranged at each position of the form with no more than 50 W per person. The CO2 exhale rate should be simulated and be no less than 383 ml/min per person.

The CO2 concentration should be measured in accordance with an international standard acceptable to the Organization, (ISO 12039:2019) at a minimum of three locations:

1. top of canopy
2. head level of a seated person
3. floor level of the test liferaft

Readings of CO2 monitors at each test point should be taken at intervals not more than 60 seconds. The duration of the test may depend on the liferaft's internal volume and the simulated CO2 exhale rate. The test may end when a balancing point has been reached at which the CO2 levels remains stable.

Acceptance Criteria

The measured ventilation rate should not be less than 5 m3/hour per person for the total number of persons which the liferaft is permitted to accommodate, or the means of ventilation should provide sufficient air to prevent CO2 concentration from exceeding a time-weighted average concentration of 5,000 ppm over a period of two hours.

The means of ventilation should be operable from inside the liferaft and be arranged to ensure that the liferaft is ventilated without stratification or formation of unventilated pockets.

If the means of ventilation is powered, sufficient energy shall be provided for a period of not less than 24 hours.

Significant Test Data

Table 1: Ventilation Performance Test Report