There are 42 outdoor warning sirens serving the City of Stillwater and the Oklahoma State University campus. Of the 42 sirens, 38 are owned by the City and 3 are owned by the University. Twenty-seven of the city-owned sirens have been installed since 1995. The University replaced their sirens in 1999 with the same make and model installed by the city. One university siren is located on top of the Life Science West building, one is located on top of the University Police Department building and one is located at the intersection of McElory and Walnut.

The 3 university-owned sirens provide coverage for the entire main OSU campus and student housing area as well as some of the adjoining privately owned properties. (See Map for coverage areas).

The new style sirens have the following features. Each siren is radio controlled and operates off of 2 deep cycle wet cell batteries that are kept charged by a 110 VAC floating DC charger. In addition each siren is two-way status. This allows the siren to communicate with the Stillwater Emergency Operations Center (EOC) over a radio frequency reporting such things as loss of power, low battery voltage, or an intrusion if someone opens one of the cabinets.

All 42 sirens are activated by agreement with the OSU Environmental Safety Services and the Stillwater Emergency Coordination and Communications Center from the Stillwater Emergency Operations Center (EOC) located in the basement of the Municipal building. In addition, the University is planning to install a second encoder like the one used by the city to activate the sirens in the event the city equipment is out of service.

Outdoor warning sirens were introduced in the early 1950's as a method of warning the American citizens of an impending attack by a foreign enemy. They were also funded by the Federal government and therefore the sounds used were chosen by the government. They chose an alternating wail as the attack warning and a three minute steady sound as the all clear. Because of this, communities throughout the United States started using the steady sound as a Tornado warning and in some communities they also used this same sound to notify their volunteer fire fighters of a fire. There no longer seems to be a concern of a threat from another country, and the government no longer offers financial assistance in purchasing warning sirens.

It is found that the new sirens have a much higher frequency range at the top end than the older sirens. This has caused some concern with the public being able to hear the siren after it has reached its highest range. This seems to be especially true with the older population. Because of this the City of Stillwater is changing the sound used for a Tornado warning from the 3 minute steady sound to a 3 minute alternating sound. THERE IS NO ALL CLEAR SOUNDED BY THE OUTDOOR WARNING SIRENS. The all clear will be made over the local radio stations and cable TV.

As a footnote, a survey was taken of 11 cities in Oklahoma requesting the number of sirens they have and the square miles within their city limits. Not including Tulsa and Oklahoma City, here are the results:

Prepared by Ralph McFadden
Director, Emergency Coordination & Communications