Abstract
The effects of nuclear spin on the observed relaxation constants of 2P1/2,3/2 alkali-metal resonance levels are calculated. While the primary interest is in obtaining correction factors for the Hanle effect measurements, the nuclear spin effects on experimental measurements by other techniques are also discussed and it is shown that some apparent discrepancies in the literature may be resolved. The experimental data for sodium and rubidium perturbed by the rare gases are discussed critically as examples of small and large fine structure respectively.