Mutual Aid Box Alarm System
The Mutual Aid Box Alarm System (known as MABAS) Senate Bill SB 642 was approved by the Wisconsin State Legislature and signed by Governor Jim Doyle on April 5, 2006. MABAS is a mutual aid measure that may be used for deploying fire, rescue, and emergency medical services personnel in a multi-jurisdictional and/or multi-agency response.

Participation in the mutual aid program is voluntary. Equipment, personnel, or services provided under MABAS are at no charge between municipalities. Expenses recovered from the responsible parties are equitably distributed. In addition, emergency personnel that respond to the emergency remain employees of their initial department or agency.


MABAS is broken into divisions rather than regions. The Thiensville Fire Department is a member of Ozaukee County MABAS division 119. When an incident exceeds the available resources available in Thiensville, the incident commander requests a MABAS Box Card.