Outdoor warning siren update, or …
What are those yellow signs?
The outdoor warning siren project, approved by voters in March along with road projects throughout Norman, is moving briskly along. The goal is to have the system in place for the spring 2011 severe weather season. Today I talked with the City of Norman’s fire chief, James Fullingim to see where we are in the process.
On August 9 they began doing individual site surveys, starting in northeast Norman and working southwestward. The goal is complete siren coverage of all of Norman, using existing public property and public easements as much as possible. The site surveys involve an acoustic engineer, assessing for radio reception, obstructions to sound travel, such as trees and lay of the land, and access. I was surprised to hear that top of a hill does not necessarily mean great radio reception.
After a site has been reviewed and selected, they place a yellow sign in the ground to identify it. The sign identifies the location and is put in place four to six weeks before any siren is installed. It gives contact information for questions and concerns. Adjacent residents and businesses will be contacted and receive direct notification of the installation. So far, they have identified about 20 locations in east Norman, though I don’t know exactly what they are at this point.
The first sirens should be installed and operational by mid-September.
This week they will be identifying potential siren sites within Lake Thunderbird State Park.
Several excellent features of the system:
–Ability to activate sirens by sub-area, so that only parts of the city under threat would hear sirens;
–A voice messaging capacity, so that specific instructions could be given if necessary. Other than on test days, it would be used very sparingly, but imagine if there were a wildfire and you needed to know which way to get out of the area;
–Solar panels on all sirens, which will be a big cost savings and allow some flexibility;
–They will be 55 foot tall concrete poles, which I hear will look pretty streamlined;
– The sirens will cover all of Norman.
Two other things I found interesting: Sirens are required to be a certain volume greater than ambient noise so that sirens in town where the ambient noise level may be 25 decibels will be quite a bit louder than those out east, where the ambient level may be 2 decibels, AND they have to be closer together in town to overcome that ambient racket!
