Products (tools, equipment, supplies) designed for reducing physical workload, accident risks, and working time are a great mean for improving work conditions and productivity. However, how good is the product when used in real context and how to evaluate it, are questions that remain for developer companies, customers and users. This paper addresses both of these questions with the example of a chemical product used in washer-disinfectors in Central Sterile Supply Departments. A proposal of understanding technology as a group of practices (installation, use, evaluation) is introduced, including measurement systems such as CUELA. To understand a ¿simple¿ product as part of broader technology and through a group of practices allows for a more comprehensive evaluation, taking the advantages of different and complementary approaches.