From the NWS Little Rock website comes this interesting section about warning sirens:
"...OUTDOOR TORNADO SIRENS...
MANY TOWNS AND COUNTIES IN ARKANSAS HAVE ACQUIRED OUTDOOR WARNING
SIRENS TO ALERT THE PUBLIC WHEN TORNADOES THREATEN. WHEN THESE
SIRENS ARE KEPT IN PROPER WORKING ORDER...THEY DO THEIR JOB AS
EXPECTED AND HELP WARN THE PUBLIC.
BUT...MANY PEOPLE DO NOT UNDERSTAND THE PURPOSE OF THESE SIRENS
AND HAVE FALSE EXPECTATIONS OF THEM.
THE COMPANIES THAT MANUFACTURE THE SIRENS CLEARLY STATE IN THEIR
SALES BROCHURES THAT THE SIRENS ARE INTENDED FOR OUTDOOR WARNING
PURPOSES. NOTE ESPECIALLY THE WORD -OUTDOOR-.
THE SIRENS ARE THUS INTENDED TO ALERT PEOPLE INVOLVED IN OUTDOOR
SPORTS...YARDWORK...RECREATIONAL ACTIVITIES...AND SO FORTH.
THE SIRENS ARE NOT DESIGNED TO...
WAKE UP PEOPLE WHILE THEY ARE SLEEPING
ALERT MOTORISTS WHO HAVE THEIR WINDOWS ROLLED UP AND THE RADIO
PLAYING
ALERT PEOPLE WHO ARE IN THEIR HOUSES WITH APPLIANCES ON OR
RADIOS OR TELEVISIONS PLAYING
ALERT PEOPLE INDOORS IN SIMILAR SITUATIONS
EACH SIREN HAS A DESIGNATED RANGE OVER WHICH IT CAN BE HEARD...
AND THIS RANGE DIFFERS FROM ONE TYPE OF SIREN TO ANOTHER.
IN ARKANSAS...THE DECISIONS TO BLOW THE SIRENS ARE MADE BY
DESIGNATED CITY OR COUNTY OFFICIALS...NOT THE NATIONAL WEATHER
SERVICE.
SIREN MANUFACTURERS ALSO MAKE SIRENS DESIGNED FOR INDOOR
COMMERICAL USES. FOR EXAMPLE...A LARGE NOISY FACTORY MIGHT NEED
BOTH AUDIBLE AND VISUAL ALERTS."
-above text from (
visit link)