Handling hydrogen systems

Current compressors are likely to be inadequate for handling high volume, high pressure hydrogen systems. 

The two ATEX directives and their national implementation are the main regulations, but not the only ones. Since hydrogen is flammable, it also falls within the rules for handling and transport of dangerous substances and goods. Furthermore, provisions for pressure vessels and pressure equipment are applicable, since hydrogen systems usually operate under an overpressure of more than 50 kPa (0.05 MPa). 

Section 11.4.2 describes membrane-cell hydrogen systems in which the cells can operate under positive pressures to make some aspects of hydrogen handling easier and safer. Section 11.4.3 is dedicated to diaphragm-cell systems. 

For leaks on liquid hydrogen systems, observe the same precautions noted above. Isolate and restrict unauthorized access to the area. Eliminate any ignition sources in the immediate area of the leak. Immediately notify your hydrogen supplier for assistance or instmctions. Proper PPE should be used before attempting to handle or repair any leak. 

The one recent improvement for handling of flammable gases is the restricted flow orifice. While this was originally designed for use with silane, it would lessen the fire hazard of any flammable gas. The restricted flow orifice is normally designed for 30 liters per minute but it is questionable how that number came about. If a hydrogen system uses 50 liters per minute, it certainly shouldn t be designed for 30 liters per minute. On the... 

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