The paper deals with the development of an SAE Recommended Practice. It includes the identification of the problem, the formation of the Task Group and the definition of the purpose. It proceeds into the structure of and summarizes the document, and gives an example of one of the important considerations: Reynolds number. In this example, the author illustrates the problem of room temperature flushing, and points out that effective flushing should be done at a Reynolds number which is turbulent and which exceeds the maximum Reynolds number that the system will experience under actual field conditions. The paper concludes with a discussion of the ballot results and a request for feedback of significant findings.