All examinations shall be impartial, fair, and practical, designed only to test the relative qualifications and fitness of applicants to discharge the duties of the particular employment which they seek to fill. No question on the examination shall relate to the political or religious convictions or affiliations of the applicant. All applicants for positions of trust and responsibility shall be specially examined as to moral character, sobriety, and integrity, and all applicants for position requiring special experience, skill, or faithfulness shall be specially examined in respect to those qualities. It shall be the duty of the sheriff and of any employee to act as an examiner or assistant examiner, at the request of the commission, without special compensation therefor. The members of the commission collectively or individually may act as examiners or assistant examiners.
Notice of the time, place, and scope of each examination shall be given by publication and posting as specified in section 387.36, and by mailing such notice to each applicant upon the appropriate list of the application register ten days in advance. The names of those found eligible upon examination, after giving credit for character and previous successful experience, shall be entered with their address and percentages on the eligible register. No name shall remain upon the eligible register more than two years without a new application, and if the rules of the commission so require, a new examination. When a vacancy has been filled or new appointment made, the names selected shall be stricken from the eligible register and transferred to the service register.