[en] Hyperfine lines associated with the X¹Σ⁺ (0-0) and (0-1) bands of H¹²⁷I are generated. Discussion of the HI line parameters in the HITRAN and SAO databases is presented. The new (0-0) line parameters are based on previously published far-infrared constants. High-resolution laboratory spectra in the infrared fundamental band region are presented and analyzed for new fine structure spectroscopic constants, which are combined with available hyperfine structure constants for calculating the new (0-1) line parameters. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)