Minn. Stat. § 43A.321: VOLUNTEER FIREFIGHTER AND RESCUE WORKERS; AGREEMENTS.

(a) An employee may reach an agreement with the employee's appointing authority to respond to emergency calls as a volunteer emergency fire or rescue worker during working hours, provided that:

(1) the employee does not respond to a call when the employee's sudden absence would endanger others; and

(2) the employee remits to the appointing authority any compensation received for responding to the call.

(b) If such an agreement is entered into:

(1) the appointing authority shall make no deductions from the employee's wages or sick or vacation time for time spent responding to calls; and

(2) workers' compensation liability is the responsibility of the entity for which the emergency services are provided while the employee is responding to the call.