The present work fosters experimental measurements and mathematical modelling techniquesto primarily determine the thermal and the relative humidity characteristics in theair-conditioned surgical operating room. The present work also demonstrates the effect ofthe various designs of surgical operating rooms and operational parameters on the flowpattern and temperatures characteristics. This study is a part of a more comprehensiveinvestigation of the more important factors affecting the air environments in surgicaloperating room. Measured and predicted temperatures and relative humidity profiles areshown to be in good agreement. The present paper introduces several recommendationsregarding the optimum design requirements of operating rooms to provide hygiene andcomfort environment. Low humidity affects comfort and health. The present work offersexamples of measured relative humidity profiles in an operating room in (New Kasr El-AiniTeaching Hospital – 1200 beds – Cairo University – Egypt). These experimental results werecarried out to verify the proposed numerical procedure and particularly in the vicinity ofthe supply outlets and operating table.