Fuel cell cartridges containing hydrogen in a metal hydride transported under this entry shall have a water capacity less than or equal to 120 mL. The pressure in the fuel cell cartridge shall not exceed 5 MPa at 55°C. The design type shall withstand, without leaking or bursting, a pressure of two (2) times the design pressure of the cartridge at 55°C or 200 kPa more than the design pressure of the cartridge at 55°C, whichever is greater. The pressure at which this test is conducted is referred to in the Drop Test and the Hydrogen Cycling Test as the "minimum shell burst pressure".

Fuel cell cartridges shall be filled in accordance with procedures provided by the manufacturer. The manufacturer shall provide the following information with each fuel cell cartridge:

.1 Inspection procedures to be carried out before initial filling and before refilling of the fuel cell cartridge;

.2 Safety precautions and potential hazards to be aware of; 

.3 Method for determining when the rated capacity has been achieved;

.4 Minimum and maximum pressure range;

.5 Minimum and maximum temperature range; and

.6 Any other requirements to be met for initial filling and refilling, including the type of equipment to be used for initial filling and refilling.

The fuel cell cartridges shall be designed and constructed to prevent fuel leakage under normal conditions of transport. Each cartridge design type, including cartridges integral to a fuel cell, shall be subjected to and shall pass the following tests:


Drop test

A 1.8 m drop test onto an unyielding surface in four different orientations:

.1 Vertically, on the end containing the shut-off valve assembly;

.2 Vertically, on the end opposite to the shut-off valve assembly;

.3 Horizontally, onto a steel apex with a diameter of 38 mm, with the steel apex in the upward position; and

.4 At a 45º angle on the end containing the shut-off valve assembly.

There shall be no leakage, determined by using a soap bubble solution or other equivalent means on all possible leak locations, when the cartridge is charged to its rated charging pressure. The fuel cell cartridge shall then be hydrostatically pressurized to destruction. The recorded burst pressure shall exceed 85% of the minimum shell burst pressure.


Fire test

A fuel cell cartridge filled to rated capacity with hydrogen shall be subjected to a fire engulfment test. The cartridge design, which may include a vent feature integral to it, is deemed to have passed the fire test if:

.1 The internal pressure vents to zero gauge pressure without rupture of the cartridge; or

.2 The cartridge withstands the fire for a minimum of 20 minutes without rupture.


Hydrogen cycling test

This test is intended to ensure that a fuel cell cartridge design stress limits are not exceeded during use. 

The fuel cell cartridge shall be cycled from not more than 5% rated hydrogen capacity to not less than 95% rated hydrogen capacity and back to not more than 5% rated hydrogen capacity. The rated charging pressure shall be used for charging and temperatures shall be held within
the operating temperature range. The cycling shall be continued for at least 100 cycles.

Following the cycling test, the fuel cell cartridge shall be charged and the water volume displaced by the cartridge shall be measured. The cartridge design is deemed to have passed the hydrogen cycling test if the water volume displaced by the cycled cartridge does not exceed the water volume displaced by an uncycled cartridge charged to 95% rated capacity and pressurized to 75% of its minimum shell burst pressure. 


Production leak test

Each fuel cell cartridge shall be tested for leaks at 15°C ± 5°C, while pressurized to its rated charging pressure. There shall be no leakage, determined by using a soap bubble solution or other equivalent means on all possible leak locations.

Each fuel cell cartridge shall be permanently marked with the following information:

.1 The rated charging pressure in megapascals (MPa);

.2 The manufacturer's serial number of the fuel cell cartridges or unique identification number; and

.3 The date of expiry based on the maximum service life (year in four digits; month in two digits).