| AFC | alkaline electrolyte fuel cell |
| ATEX | ATmosphères EXplosibles (Explosive atmospheres) |
| BRHS | Biennial Report on Hydrogen Safety |
| C | Hydrogen concentration by volume v/v |
| CE | Conformité Européenne/European Conformity (the marking used to show conformity with a European Directive) |
| CEA | Commissariat à l'énergie atomique |
| CFD | computational fluid dynamics |
| CHP | combined heat and power |
| CNG | compressed natural gas |
| EC | European Commission |
| FC | Fuel cell |
| f | Part of the enclosure containing the homogenous H2 –air mixture |
| FP6 | Sixth framework programme |
| FZK | Forschungszentrum Karlsruhe |
| EHSR | essential health and safety requirements |
| EIGA | European Industrial gases Association |
| EMC | Electromagnetic Compatibility Directive |
| EN | European norm (standard) |
| EU | European Union |
| GAD | Gas Appliances Directive |
| GFP | general fire precautions |
| HSE/HSL | Health and Safety Executive/Health and Safety Laboratory |
| IEC | International Electrotechnical Commission |
| IPG | Installation Permitting Guidance |
| ISO | International Standards Organisation |
| KI | Kurchatov Institute |
| LEL | lower explosion limit |
| LES | Large Eddy Simulation |
| LOC | limiting oxygen concentration |
| LPG | liquefied petroleum gas |
| LVD | Low Voltage Directive |
| MCFC | molten carbonate fuel cell |
| MSDS | materials safety data sheet |
| NASA | National Aeronautics and Space Administration |
| NCSRD | National Center for Scientific Research Demokritos |
| NFPA | National Fire Protection Association |
| PACF | phosphoric acid fuel cell |
| PED | Pressure Equipment Directive |
| PEMFC | polymer electrolyte membrane fuel cell |
| PFP | process fire precautions |
| PS | Pro-Science |
| RANS | Reynolds Averaged Navier Stokes |
| SNL | Sandia National Laboratories |
| SOFC | solid oxide fuel cell |
| STREP | Specific Targeted Research project |
| UEL | upper explosion limit |
| UNIMAN | University of Manchester |
| UNIPI | University of Pisa |
| UU | University of Ulster |
| WP | Work Package |