CPG 1-17 recommends that a monthly test be conducted, consisting of the steady "attention" signal for no more than one minute, one minute of silence, and the "attack" signal for no more than one minute. A "growl test" signal is also described by CPG 1–17, when a siren must be tested more than once a month. This is typically a 1-second burst of sound to verify the proper operation of the siren without causing a significant number of people to interpret the test as an actual alert. Many cities in the U.S. periodically sound their sirens as a test, either weekly, monthly, or yearly, at a day and hour set by each individual city.
CPG 1-17 recommends that a monthly test be conducted, consisting of the steady "attention" signal for no more than one minute, one minute of silence, and the "attack" signal for no more than one minute A "growl test" signal is also described by CPG 1–17, when a siren must be tested more than once a month. This is typically a 1-second burst of sound to verify the proper operation of the siren without causing a significant number of people to interpret the test as an actual alert. Many cities in the U.S. periodically sound their sirens as a test, either weekly, monthly, or yearly, at a day and hour set by each individual city.