669.24  State volunteers.
  A person who performs services for the state government or any agency or subdivision of state government and who does not receive compensation is not personally liable for a claim based upon an act or omission of the person performed in the discharge of the person’s duties, except for acts or omissions which involve intentional misconduct or knowing violation of the law, or for a transaction from which the person derives an improper personal benefit. For purposes of this section, “compensation” does not include payments to reimburse a person for expenses.
87 Acts, ch 212, §1
CS87, §25A.24
C93, §669.24