This story has been updated.
Entergy officials said technicians will investigate the cause of two siren failures and make any needed repairs after they failed to work during a siren sound test at the Indian Point Power Plant.
Of 172 sirens throughout the Hudson Valley, 170 performed as required for four full minutes between 10:30 and 11 a.m. Wednesday in Westchester, Rockland, Putnam, and Orange counties. The two sirens that failed were located in Putnam and Orange counties.
The sirens are not a signal to evacuate. In an actual emergency, the sirens would sound at full volume to alert residents to tune in to a local radio or television station for directions and information.
Residents in Putnam and Orange counties have no need to be concerned, the company said.
"In the unlikely event of an emergency that required the sounding of sirens followed by a siren failure, the county would then utilize CodeRed calls to the people who live and work in the area around that siren," said Entergy spokesman Jerry Nappi.
CodeRed is essentially a reverse 911 system that can direct dial an identified population for during emergencies, he added.
The plant generates more than 30 percent of the electricity used by New York City and Westchester County. It is scheduled to close by 2021 according to an agreement between Gov. Andrew Cuomo and Entergy.
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