Pasadena's fire and police departments have a sophisticated phone system called PLEAS that is capable of calling hundreds of Pasadena residents and business owners per hour.

During a substantial threat to life or property, the system is able to map out a specific geographic area and list the phone numbers for properties in that area. An emergency message is recorded and relayed to every phone number on the list.

The system has several safeguards to make sure it reaches as many people as possible including unlisted numbers for emergency purposes only. The system can also detect whether it has reached a person, data line, fax line or voice mail, and plays messages accordingly. It can also detect which lines are out of order or busy, and will call busy numbers many times at set intervals before giving up.

If you receive a call, listen for this phrase: “This is an official alert from the city of Pasadena.” Then listen for instructions. Let your family members and employees know announcements are usually in English only, and instruct children to have an adult in the house listen to the message.

Be sure not to attach an electronic anti-telemarketing device to your phone, which can interfere with incoming emergency announcements. Instead, place your phone number on the National Do Not Call Registry at 888-382-1222 or at www.DoNotCall.gov.