Students who are funded through a graduate research assistantship (GRA) need to discuss with their advisor any research activities outside the lab as well as any consulting activities. GRAs should also discuss with their advisor any additional classes they intend to take, or any extra teaching/TAing, beyond those needed to fulfill the PhD program requirements. In addition to slowing degree progress, such outside activities may imperil progress on the externally-funded project supporting the student and subject the laboratory or advisor to unpleasant consequences from the grant agency or sponsor. Core and elective courses taken for the breadth requirement, including any research activities as part of those courses, or teaching/TAing as part of the degree requirements, are not of concern.
Faculty who are approached by GRAs from outside their lab regarding additional research, teaching/TAing, classes, consulting, etc. should inform the advisor (both research and departmental advisors, if different).
[Change notes: Removed inexplicable "here is another test".]