The U.S. Nuclear Regulatory Commission (NRC) is amending its spent fuel storage regulations by revising the TN Americas LLC Standardized Advanced NUHOMS[supreg] Horizontal Modular Storage System (NUHOMS[supreg] System) listing within the "List of approved spent fuel storage casks" to include Amendment No. 4 to Certificate of Compliance No. 1029. Amendment No. 4 revises the certificate of compliance's technical specifications to: clarify the applicability of unloading procedures and training modules relative to spent fuel pool availability; credit the use of the installed temperature monitoring system specified in lieu of performing daily visual vent inspections; establish dose rates on the front inlet bird screen and the door of the concrete storage module for the Advanced Horizontal Storage Module; modify the criteria for performing Advanced Horizontal Storage Module air vent visual inspections; identify the blocked vent time limitations for each of the 24PT1 and 24PT4 dry shielded canisters; and provide a new temperature rise value for the Advanced Horizontal Storage Module with a loaded 24PT4 dry shielded canister.