(a) Except as otherwise provided by this chapter, this chapter applies to:
(1) an insurer authorized to engage in the business of accident and health insurance in this state, including:
(A) a life, health, and accident stock insurance company;
(B) a mutual insurance company, including:
(i) a mutual life insurance company; and
(ii) a mutual assessment life insurance company;
(C) a local mutual aid association;
(D) a mutual or natural premium life or casualty insurance company;
(E) a general casualty company;
(F) a nonprofit hospital, medical, or dental service corporation, including a corporation operating under Chapter 842;
(G) a multiple employer welfare arrangement that holds a certificate of coverage under Chapter 846;
(H) a Lloyd's plan operating under Chapter 941;
(I) a reciprocal or interinsurance exchange operating under Chapter 942; and
(J) any other type of insurer required by law to be authorized by the department to issue accident and health insurance policies; and
(2) a health maintenance organization operating under Chapter 843.
(b) This chapter applies to a third-party administrator acting on behalf of an accident and health insurer.