Safe storage of compressed gas cylinders

Protection goals and minimum requirements

Safety cabinets for the storage of compressed gas cylinders in accordance with DIN EN 14470-2 must be designed and constructed in such a way that in the event of fire the contents do not pose any additional risk of fire spreading. The fire resistance should enable the personnel to leave the working area and the fire brigade to reach the area and contain the fire before the compressed gas cylinders become unstable. In addition, for health and explosion protection, small gas emissions inside the cabinet must be extracted.

Excerpts from the DIN EN 14470-2

Ventilation

• The cabinets must be provided with air inlet and outlet openings to allow connection to an exhaust air system.
• The exhaust air flow must ensure that small gas emissions inside the cabinet are extracted.
• For efficient purging, the air exchange rate must be at least 10 times when storing flammable and oxidizing gases and 120 times for toxic gases.
• Ventilation must be provided in the upper and lower parts of the cabinet.
• The pressure drop in the cabinet must not exceed 150 Pa.

Gas and electricity pipelines

• The number of gas and electric lines shall be limited to the minimum necessary.
• A maximum of three gas lines with Ø 10 mm and two electric lines with Ø 20 mm are permitted per compressed gas cylinder.
• For the best possible fire resistance, pipes made of stainless steel or a material with similar thermal conductivity are recommended.
• Unused feedthroughs must be closed according to the manufacturer's instructions.

Fire chamber test

• Each cabinet model is type-tested in a fire chamber according to DIN EN 14470-2 type G90/type G30.

Storage capacity

• The maximum storage capacity per safety cabinet including purge gas is 220 litres, a maximum of four gas cylinders with 50 litres each or up to three gas cylinders with 70 litres each.
• The compressed gas cylinders in the cabinet may be in use.

Insertion, removal and fastening

• An access ramp or mechanical lifting device may be used, but it must not be made of aluminium.
• A suitable fastening system must be installed in the cabinet to prevent the compressed gas cylinders from falling over.

Extracts from DIN EN 14727 or, more recently, DIN EN 16121 and DIN EN 16122

Static endurance test

• Shelves, e.g. intermediate floors, are subjected to a static load and impact test and must not show any breakage or other damage.

Dynamic load test

• All mechanical (movable) components such as doors are tested with 50,000 cycles each. After the tests, the doors must close and engage precisely.