(1) The State Fire Marshal, first assistant fire marshal, and deputies shall each have the power in any county of the State of Nebraska to summon and compel the attendance of witnesses before them, or any of them, to testify in relation to any matter which is by the provisions of sections 81-501.01 to 81-531 a subject of inquiry and investigation, and may require the production of any book, paper, or document deemed pertinent thereto by them or any of them. Such summons shall be served in the same manner and have the same effect as subpoenas from district courts. All witnesses shall receive the same compensation as is paid to witnesses in district courts, with mileage to be computed at the rate provided in section 81-1176 for state employees, which shall be paid out of the State Fire Marshal Cash Fund upon vouchers signed by the State Fire Marshal, first assistant fire marshal, or deputy before whom any witnesses shall have attended. Such officer shall, at the close of the investigation wherein such witness was subpoenaed, certify to the attendance and mileage of such witness and file such certificate in the office of the State Fire Marshal. All investigations held by or under the direction of the State Fire Marshal or his or her subordinates may be private, and persons other than those required to be present may be excluded from the place where such investigation is held. Witnesses may be kept separate and apart from each other and not allowed to communicate with each other until they have been examined.

(2) The State Fire Marshal, first assistant fire marshal, and deputies are each authorized and empowered to administer oaths and affirmations to any persons appearing as witnesses before them, and false swearing in any manner or proceeding aforesaid shall be deemed perjury and shall be punished as such upon conviction in any court of competent jurisdiction.

(3) Any witness (a) who refuses to be sworn, (b) who refuses to testify, (c) who disobeys any lawful order of the State Fire Marshal, first assistant fire marshal, or deputy in relation to any investigation, (d) who fails or refuses to produce any paper, book, or document touching any matter under examination, or (e) who commits any contemptuous conduct after being summoned to appear before the State Fire Marshal, first assistant, or deputy to give testimony in relation to any matter or subject under examination or investigation as aforesaid shall be subject to conviction for contempt and, upon conviction of such contempt before any court of competent jurisdiction, shall be punished as provided by law for contempt of the orders of a district court, except that no person shall be compelled to give testimony which might tend to incriminate him or her or to give testimony which is considered privileged by the laws of the State of Nebraska.