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Hydrogen explosion

NFPA 704
"fire diamond"
Flammability code 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g., propane Health code 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g., sodium chloride Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
The fire diamond hazard sign for both elemental hydrogen gas and its isotope deuterium.

Hydrogen safety covers the safe production, handling and use of hydrogen - particularly hydrogen gas fuel and liquid hydrogen. The main concern in working with hydrogen is flammability.

Hydrogen possesses the NFPA 704's highest rating of 4 on the flammability scale because it elemental form of H2 hydrogen gas flameable when mixed even in small amounts with ordinary air; hydrogen gas and normal air can ignite at as low as 4% air due to the oxygen in the air and the simplicity and chemical properties of the reaction. However, hydrogen has no rating for innate hazard for reactivity or toxicity. The storage and use of hydrogen poses unique challenges due to its ease of leaking as a gaseous fuel, low-energy ignition, wide range of combustible fuel-air mixtures, buoyancy, and its ability to embrittle metals that must be accounted for to ensure safe operation. Liquid hydrogen poses additional challenges due to its increased density and the extremely low temperatures needed to keep it in liquid form.

Hydrogen codes and standards are codes and standards (RCS) for hydrogen fuel cell vehicles, stationary fuel cell applications and portable fuel cell applications.

Additional to the codes and standards for hydrogen technology products, there are codes and standards for hydrogen safety, for the safe handling of hydrogen and the storage of hydrogen.


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