tokens: Qualification testing of the mechanism or of mechanical subsystem shall be considered successful when all the following criteria are demonstrated at the end of the test : 1 . No direct contact between metallic parts in relative motion identified in the interface of solid lubricated contact surfaces ; 2 . Surface properties of contact surfaces not modified beyond the specified limits of their performance properties ; 3 . No chemical deterioration beyond the specified limits of fluid lubricants is found , and anti - creep barrier , when present , are still operational ; 4 . The amount and size of wear products conforms to contamination and overall mechanism performance requirements specified in the specific mechanism specification ( SMS ) ; 5 . Worst - case variation or degradation peak torque or force overall throughout qualification , including life , testing is compatible with the functional dimensioning requirements specified in clause 4.7.5.3 ; 6 . Deterioration torque or force performance is less than or equal to 50 % of the values measured at the beginning of qualification tests ; 7 . Other degradation factors agreed on a case by case basis with the customer are within the specified limits ; 8 . All measured performances conform to the requirement of the specific mechanism specification .