The currently used methods of ergonomic assessment of protective clothing depend on the subjective feeling of research participants and don’t take into consideration all aspects of its use. Therefore, more amount of work is undertaken toward the development of new research tools for the ergonomic assessment of protective clothing. Research was carried out at the Central Institute for Labour Protection – National Research Institute in Lodz. A new methodology will take into consideration a variant of reference clothing, which is related to the results of ergonomics research of protective clothing. Preparation of the reference clothing initiated by picking the appropriate fabric is based on the results of parameters influencing the physiological comfort and sensorial comfort. In the current part, results of different fabric parameters are presented, which are related to physiological comfort, i.e., the thermal resistance, water vapor resistance, hygroscopicity, and air permeability. In the next part of research, we will focus on the parameters related to objective sensorial feelings, i.e., total hand value and its components. Seven fabrics, including six cotton/polyester fabrics, diverse in terms of constituent fiber content and structure parameters (weave, thread density per 1 dm, thread linear density, mass per square meter, thickness), and Tencel/polyester fabric were tested. The best in terms of thermal resistance, water vapor resistance, and air permeability was the cotton/polyester fabric (35% cotton/65% PES) with the smallest mass per square meter. This fabric also exhibits the high hygroscopicity of 7.5%, which puts it into the fourth position.