The warning sirens employ the latest technology to ensure their operation and dependability.
Each has a battery back-up source of power for operation and is activated by radio signals. A computer component at each location immediately verifies that the siren has received the activation signal and is operating properly.
The siren network is intended to alert residents who are outside their residence or place of work. While they may be audible indoors, noise levels inside a building greatly affect a resident's ability to hear the outdoor warning devices.
The sirens are tested on the first Wednesday of every month at Noon, unless there is an active storm threat or other inclement weather situation. This is standard testing procedure in every county in Ohio. Good details about testing are on the Hamilton County Emergency Management and Homeland Security website: