This work is in the general research area of distance teaching; more specifically we are trying to design a virtual laboratory platform on the web to be able to do distant practical work in a cooperative environment. In this paper we present the contribution of virtual reality to the design of ergonomic interfaces which allow instructors and learners to work in a collaborative environment to do practical work. The aimed objective by the virtual reality in the conception of ergonomic interfaces of virtual environment is to create scenarios close to the real world which will permit the learners to immerse in this environment to do their activities.