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Today, the Clean Vehicle Education Foundation (CVEF) issued a Safety Alert after receiving reports of the unintended activation of rupture disc style pressure relief devices (PRDs) on cylinder valves marked in accordance with the European requirements for vehicles with 200 bar service pressure (3,000 psi). These occurrences are alarming because unintended activations had not been reported since development and first adoption of ANSI PRD1 in 1998. An unintended activation releases the entire contents of a CNG cylinder within a minute or two with far more severe potential consequences than a smaller leak. Had these vehicles been inside a building at the time of the unintended release, a large cloud of natural gas would have formed with high risk of a serious fire. As noted in the CVEF Safety Alert, European or global CNG components that are not designed and marked for the higher service pressure of 3,600 psi used in the U.S. should not be used here. CVEF has reports that some distributors in the U.S. have sold—and are still selling—these underrated components. The Alert makes a number of recommendations concerning discontinuing use of these underrated valves and removal/replacement of these units in existing vehicles. A copy of the Alert is posted on the CVEF and NGVAmerica websites, and will be distributed immediately to OEMs, SVM system manufacturers and their installers, and fleet operators.