With an increasing number of projects involving production and use of low-carbon hydrogen, the compatibility of assets for storage and transport of hydrogen gas shall be guaranteed. Fracture toughness resistance and corrosion fatigue behavior of a selection of seamless pipes for OCTG, pipeline and pressure vessels, in pressurized H2 service, is investigated. Fracture toughness evaluations were performed via fatigue pre-cracked bolt-load specimens exposed to 100 bar hydrogen gas during 1000 h at room temperature. All materials presented hydrogen stress intensity factor thresholds KIH largely above 55 MPa.m1/2, compliant with the ASME B31.12 option B requirement that defines materials requirements for hydrogen service. Corrosion fatigue tests were performed on compact tensile specimens, also prior pre-cracking. Fatigue crack growth rate measurements were determined from 0.01 to 30 Hz and load ratios at 0.1 or 0.9 for covering applications susceptible to present very different internal pressure variations during service life. A focus is given on the influence of load ratios on threshold ΔK for initiating fatigue in presence of hydrogen. Data provided can be used for building Failure Assessment Diagram, decisive tool for predicting the safe domain of usage of structures.