In this work, a method previously proposed in the literature (Sisto R, Pinto I, Stacchini N et al. Infrared radiation exposure in traditional glass factories. AIHAJ 2000; 61: 5-10) to evaluate the exposure to infrared (IR) radiation when the source can be approximated as a black body is implemented in a mathematical code developed in Matlab. Some practical situations are discussed. A comparison between the results obtained by a spectroradiometric technique and that obtained by using a broadband radiometer and the modelling of the source is shown. The IR radiation exposure evaluations in a cement industry and in a steel forge are shown and compared to the exposure limit values.