Information to assist in evaluating the effect of solar radiation on outdoor metal-enclosed switchgear including metal-enclosed bus and control switchboards is provided in this guide. Specific data in the form of a continuous current capability factor for specific maximum monthly normal temperatures at the installation location to adjust the continuous current capability of outdoor metal-enclosed switchgear to the solar radiation condition required are given in this guide. Examples of maximum monthly normal temperatures along with sources for data for the US and for Canada are also presented in this guide.