Hydrogen Generators electrolytically break down water in to hydrogen and oxygen. Hydrogen will receive further purification through palladium permeable filters and the oxygen is vented. When used with a down stream water trapping system, such as molecular sieve trap and an indicating trap in series, a hydrogen generator will provide gas chromatography quality hydrogen for both carrier gas and detector fuel use. New models of hydrogen generators produce hydrogen at a purity of 99.9999% and internal purifiers eliminate the need for additional down stream purification. A major safety advantage for hydrogen generators is that at any time, the total volume of gas in the unit is small and the pressure is low. Most units have a pressure relief valve, set for a pressure slightly above the normal operating pressure. Other safety devices within the generator also ensure that pressures cannot exceed the specified maximum and shut down the unit if the pressure suddenly stops.