This standard presents metallic material requirements for resistance to sulfide stress cracking (SSC) for petroleum production, drilling, gathering and flowline equipment, and field processing facilities to be used in H2S-bearing hydrocarbon service. This standard is applicable to the materials and/or equipment specified by the materials standards Institutions listed in Table 5 (or by equivalent standards or specifications of other agencies). This standard does not Include and is not intended to include design specifications. Other forms of corrosion and other modes of failure, although outside the scope of this standard, should also be considered in design and operation of equipment. Severely corrosive conditions may lead to failures by mechanisms other than SSC and should be mitigated by corrosion inhibition or materials selection, which are outside the scope of this document. For example, some lower strength steels used for pipelines and vessels may be subjected to failure by blister cracking or stepwise cracking as a result of hydrogen damage associated with general corrosion in the presence of hydrogen sulfide. Also, austenitic stainless steels and even more highly alloyed materials may fall by a type of chloride stress corrosion cracking that la promoted by elevated temperature, aggravated in some cases by the presence of hydrogen sulfide.  Historical Document 1993