Hi, From above discussion what I understand, check list is consider to be mistake proofing or not that depends on situtation how we use. 1) If process is contineous and we check on some instances (oil leakage on visit) then check list is not a mistake proofing. 2) If process is not contineous (just instances like collecting documents) and we check on instances when it happen then chek list is mistake proofing. views pls