(b)
If a petition is filed with the Authority—
(1)
by any person alleging—
(A)
in the case of an appropriate unit for which there is no exclusive representative, that 30 percent of the employees in the appropriate unit wish to be represented for the purpose of collective bargaining by an exclusive representative, or
(B)
in the case of an appropriate unit for which there is an exclusive representative, that 30 percent of the employees in the unit allege that the exclusive representative is no longer the representative of the majority of the employees in the unit; or
(2)
by any person seeking clarification of, or an amendment to, a certification then in effect or a matter relating to representation;
the Authority shall investigate the petition, and if it has reasonable cause to believe that a question of representation exists, it shall provide an opportunity for a hearing (for which a transcript shall be kept) after reasonable notice. If the Authority finds on the record of the hearing that a question of representation exists, the Authority shall supervise or conduct an election on the question by secret ballot and shall certify the results thereof. An election under this subsection shall not be conducted in any appropriate unit or in any subdivision thereof within which, in the preceding 12 calendar months, a valid election under this subsection has been held.
(d)
The Authority shall determine who is eligible to vote in any election under this section and shall establish rules governing any such election, which shall include rules allowing employees eligible to vote the opportunity to choose—
(1)
from labor organizations on the ballot, that labor organization which the employees wish to have represent them; or
(2)
not to be represented by a labor organization.
In any election in which no choice on the ballot receives a majority of the votes cast, a runoff election shall be conducted between the two choices receiving the highest number of votes. A labor organization which receives the majority of the votes cast in an election shall be certified by the Authority as the exclusive representative.