MESA的消防回流装置改造项目就是这一过程的完美例子。自1974年以来，所有新的消防设施都被要求配备经批准的双止回防回流装置。然而，许多以前存在的消防系统并没有这样的装备。直到1991年，Mesa才能够创建包含必要元素的工具来改造这些旧服务。本文介绍了MESA成功的消防防回流装置改造项目。在实施该计划的过程中，有几个问题需要解决，比如建立MESA的法律权威以要求改造；明确规划实施的目标和程序；必须考虑为不合规行为提供后果。还报告了问题、结果、处罚和结论。

MESA's fire service backflow device retrofit program is a perfect example of this process. Since 1974 all new fire services have been required to have an approved double check backflow prevention device. However, many preexisting fire services were not so equipped. It was not until 1991 that Mesa was able to create the tool containing the necessary elements to retrofit these older services. This paper describes MESA's successful fire service backflow prevention device retrofit program. In implementing this program, several issues such as establishing the legal authority of MESA to require the retrofit; and clearly defining goals and procedures for the implementation of the program; and providing consequences for non-compliance had to be considered. Problems, results, penalties, and conclusions are also reported.