(a) A district is not liable for a claim arising from the act or omission of an employee or volunteer under an oral or written contract with the district if the act or omission:
(1) is in the course and scope of the employee's or volunteer's duties for the district;
(2) takes place during the provision of emergency services;
(3) is not in violation of a statute or ordinance applicable to emergency action; and
(4) is not wilful or wantonly negligent.
(b) This section does not expand the liability of a district.