Authority Having Jurisdiction Definition or AHJ: An entity that has the authority and responsibility for developing, implementing, maintaining, and overseeing the qualification process within its organization or jurisdiction. This may be a state or Federal agency, training commission, NGO, private sector company, or a tribal or local agency such as police, fire, or public works department. In some cases, the AHJ may provide support to multiple disciplines that collaborate as a part of a team (e.g., an IMT). SOURCE: FEMA
The Authority Having Jurisdiction could be a local municipality, the state, or at a federal level. In many cases the local fire department has AHJ.