Authorized users will be classified as either restricted or unrestricted, depending on their experience and level of skill. The restricted classification is normally reserved for newly trained users, although unrestricted users may be reclassified to restricted with lapses in use of six months or more.

Only the people who are qualified, responsible, and have taken the proper training courses will be designated as unrestricted users by the lab manager. Note that this designation carries additional responsibilities to use the equipment in a safe and efficient manner.