This paper presents comparisons of recent experimental data, presented in a companion paper, to the existing correlations for heat transfer in various gas flow regimes and development of more accurate new correlations. The existing correlation of Celeta et al. showed the best agreement with the data in the turbulent heat transfer regime, while most of the existing correlations for laminar heat transfer showed unsuccessful predictions. Three new sets of correlations, each covering the mixed convection laminar, normal turbulent and deteriorated turbulent heat transfer (DTHT) regimes for heated gas up-flow, have been developed to agree better with the data in each regime. (C) 2008 Elsevier Ltd. All rights reserved.