The provisions of this chapter, except as necessary to conduct the vote, shall not become operative until the director finds in a referendum conducted by him or her that not less than 40 percent of the handlers, as defined in Section 66532 and as determined in accordance with Section 66573, have participated and that either of the following occurs:
(a)
Sixty-five percent or more of the handlers voting marketed at least a majority of the total quantity of iceberg lettuce marketed in the preceding marketing season by all of the handlers who voted in the referendum and they voted in favor of this chapter.
(b)
A majority of the handlers voting marketed 65 percent or more of the total quantity of iceberg lettuce marketed in the preceding marketing season by all the handlers who voted in referendum and they voted in favor of this chapter.