This paper provides a concise review of 'hydrogen promoters', aqueous corrodants known to generate
hydrogen flux through mild steel at low temperatures. A new theory of hydrogen promotion will be presented.
Hydrogen promoters will be ranked according to their severity. The role of temperature, scale, surface coatings
and surface condition will also be considered.
The paper should provide useful reference material for those interested in field and laboratory measurements of
hydrogen flux, and the relation between the two.
Keywords: hydrogen flux, hydrogen flux promoter, sour corrosion