ISO 13626:2003

ISO 13626:2003 specifies requirements and gives recommendations for suitable steel structures for drilling and well-servicing operations in the petroleum industry, provides a uniform method of rating the structures, and provides two product specification levels.
ISO 13626:2003 is applicable to all new designs of all standard steel derricks, special steel derricks, portable masts and substructures.
Annex A provides a number of standard supplementary requirements which apply only if specified by the purchaser.