Requests must be submitted in writing from the Department Chief to the Cal OES, Fire and Rescue Branch for approval and processing to the attention of:
MACS 3 Letter ID Administrator
Cal OES Fire and Rescue Branch
23300 Castle Street
Riverside, CA 92518
Request letter must have a signature block for the respective Cal OES Operational Area Coordinator to sign. By signing this letter of request, the Cal OES Operational Area Coordinator is supporting the request and concurs that you meet the following:
- Must have emergency fire, rescue, and/or hazardous materials response jurisdictional responsibility.
- The Cal OES Fire and Rescue Operational Area Coordinator and/or the County Fire Chiefs Association recognize agency.
- Agency participates in the California Fire and Rescue Mutual Aid System.
- Jurisdiction must be signatory to the State Master Mutual Aid Agreement or a Federal Agency or Tribal Fire Department with fire protection responsibility.
- Must have a designated Public Safety Answering Point and/or Emergency Communication Dispatch Center.
Local jurisdictions contracting with a private contractor/vendor will use the three-letter designator assigned to that jurisdiction.
Please indicate first, second and third choice for your three-letter designator, with the 3rd letter ending in either “X", “M" or “N".
You will receive written confirmation of the three-letter designator assigned to your agency or written notice of non-approval on your request. If approved, Operations Bulletin 31 and the Cal OES Form F-5 will be included with the letter of confirmation.
Upon approval, you will be directed to submit your agency's resource information into the Mutual Aid Reimbursement System (MARS) by completing the Cal OES Form F-5 California Fire and Rescue Mutual Aid System Resources Inventory. The Operations Bulletin 31 contains directions on how to submit your agency's resource information.
