(a) A participant may appear in a proceeding in person or by an attorney or other qualified representative. An individual may appear in his or her own behalf, a member of a partnership may represent the partnership, a bona-fide officer of a corporation, trust, association or organized group may represent the corporation, trust, association or group, and an officer or employee of a State commission, of a department or political subdivision of a State or other governmental authority, may represent the State commission or the department or political subdivision of the State or other governmental authority, in any proceeding.

(b) A person compelled to appear or voluntarily testifying or making a statement before the Commission or the presiding officer, may be accompanied, represented, and advised by an attorney or other qualified representative.

(c) A person appearing before the Commission or the presiding officer must conform to the standards of ethical conduct required of practitioners before the Courts of the United States, and where applicable, to the requirements of Section 12(i) of the Public Utility Holding Company Act of 1935 (15 U.S.C. 791(i)).

(a) After a hearing the Commission may disqualify and deny, temporarily or permanently, the privilege of appearing or practicing before it in any way to a person who is found:

(1) Not to possess the requisite qualifications to represent others, or

(2) To have engaged in unethical or improper professional conduct, or

(3) Otherwise to be not qualified.

(b) Contumacious conduct in a hearing before the Commission or a presiding officer will be grounds for exclusion of any person from such hearing and for summary suspension for the duration of the hearing by the Commission or the presiding officer.

(a) No person having served as a member, officer, expert, administrative law judge, attorney, accountant, engineer, or other employee of the Commission may practice before or act as attorney, expert witness, or representative in connection with any proceeding or matter before the Commission which such person has handled, investigated, advised, or participated in the consideration of while in the service of the Commission.

(b) No person having been so employed may within 1 year after his or her employment has ceased, practice before or act as attorney, expert witness, or representative in connection with any proceeding or matter before the Commission which was under the official responsibility of such person, as defined in 18 U.S.C. 202,while.

(c) Nothing in paragraphs (a) and (b) of this section prevents a former member, officer, expert, administrative law judge, attorney, accountant, engineer, or other employee of the Commission with outstanding scientific or technological qualifications from practicing before or acting as an attorney or representative in connection with a particular matter in a scientific or technological field if the Chairman of the Commission makes a certification in writing, published in the Federal Register, that the national interest would be served by such action or representation.