In these industrial refrigeration applications, product refrigeration requires very varied solutions, depending on the specific need of the process. Some require significant drying in the time unit, others the guarantee of less weight loss of the stored product. The cold could also require alternate cycles or air circulation adequate for the presence of personnel or of the treated product. The process requirements for maturing, drying or smoking rooms, for cleanrooms or for processing rooms, differ a great deal in terms of material compatibility and product sanitization. For these applications, ventilated units are available with natural refrigerants such as glycol, CO₂, or synthetic refrigerants of the latest generation.