OGP report 422 presents the results of work to calibrate the partial action factors for environmental actions for ISO 19906:2010 Petroleum and natural gas industries Arctic offshore structures, with emphasis on ice actions. It also presents the calibration procedure for future reference. ISO 19906 allows a user to perform a calibration of environmental action factors for use in place of the action factors presented in ISO 19906. ISO 19906:2010 refers to this OGP report for information on the methodology of a calibration. ISO 19906:2010 also refers to this OGP report for information on the action factors calibrated for L3 structures. Consequently this OGP report is listed as a bibliographic reference, A.7-2, in ISO 19906:2010. This will provide wide international recognition for OGP's support of international standards.