The commissioner shall, by rule, promulgate standards as needed to conform state occupational safety and health standards to federal occupational safety and health standards. The commissioner shall follow the rulemaking procedures of chapter 17A, and shall file a notice of intended action within ninety days of federal publication of a new, amended, or revoked federal standard.

 The commissioner, in promulgating standards dealing with toxic materials or harmful physical agents under this subsection, shall set the standard which most adequately assures, to the extent feasible, on the basis of the best available evidence, that no employee will suffer material impairment of health or functional capacity even if such employee has regular exposure to the hazard dealt with by such standard for the period of the employee’s working life. Development of standards under this subsection shall be based upon research, demonstrations, experiments, and such other information as may be appropriate, but in any event shall conform with the provisions of subsection 1 of this section. In addition to the attainment of the highest degree of health and safety protection for the employee, other considerations shall be the latest available scientific data in the field, the feasibility of the standards, and experience gained under this and other health and safety laws. Whenever practicable, a standard promulgated shall be expressed in terms of objective criteria and of the performance desired.

 Any standard promulgated under this section shall prescribe the use of labels or other appropriate forms of warning as are necessary to insure that employees are apprised of all hazards to which they are exposed, relevant symptoms and appropriate emergency treatment, and proper conditions and precautions of safe use or exposure. Where appropriate, such standard shall also prescribe suitable protective equipment and control or technological procedures to be used in connection with such hazards and shall provide for monitoring or measuring employee exposure at such locations and intervals, and in such manner as may be necessary for the protection of employees. In addition, where appropriate, any such standard shall prescribe the type and frequency of medical examinations or other tests which shall be made available, by the employer or at the employer’s cost, to employees exposed to such hazard in order to most effectively determine whether the health of such employee is adversely affected by such exposure. The results of such examinations or tests shall be furnished to the commissioner, and if released by the employee, shall be furnished to the employee’s physician and the employer’s physician.

 The commissioner shall provide for an emergency temporary standard to take immediate effect if the commissioner determines that employees are exposed to grave danger from exposure from substances or agents determined to be toxic or physically harmful or from new hazards and if such emergency temporary standard is necessary to protect the employees from such danger. Such emergency standard shall cease to be effective and shall no longer be applicable after the lapse of six months following the effective date thereof unless the commissioner has initiated the procedures provided for under this chapter, for the purpose of promulgating a permanent standard as provided in subsection 1 of this section in which case the emergency temporary standard will remain in effect until the permanent standard is adopted and becomes effective. Abandonment of the procedure for such promulgation by the commissioner shall terminate the effectiveness and applicability of the emergency temporary standard.

 Any affected employer may apply to the commissioner for a rule or order for a permanent variance from a standard promulgated under this section. Affected employees shall be given notice of each such application and an opportunity to participate in a hearing. The commissioner shall issue such rule or order if the commissioner determines on the record, after opportunity for an inspection where appropriate and a hearing, that the proponent of the variance has demonstrated by a preponderance of the evidence that the conditions, practices, means, methods, operations, or processes used or proposed to be used by an employer will provide employment and places of employment to the employer’s employees which are as safe and healthful as those which would prevail if the employer complied with the standard. The rule or order so issued shall prescribe the conditions the employer must maintain, and the practices, means, methods, operations, and processes which the employer must adopt and utilize to the extent that they differ from the standard in question. Such a rule or order may be modified or revoked upon application by an employer, employees, or by the commissioner on the commissioner’s own motion, in the manner prescribed for its issuance under this subsection at any time after six months from its issuance.

 Where there are conflicts with standards, rules, or regulations promulgated by any federal agency other than the United States department of labor, special variances from standards, rules, or regulations promulgated under this chapter may be granted to avoid such regulatory conflicts. Such variances shall take into consideration the safety of the employees involved. Notwithstanding any other provision of this chapter, and with respect to this subsection, any employer seeking relief under this provision must file an application with the commissioner and the commissioner shall forthwith hold a hearing at which employees or other interested persons, including representatives of the federal regulatory agencies involved, may appear and, upon the showing that such a conflict indeed exists, the commissioner may issue a special variance until the conflict is resolved.

 In determining the priorities for establishing standards under this section, the commissioner shall give due regard to the urgency of the need for mandatory safety and health standards for particular industries, trades, crafts, occupations, businesses, workplaces or work environments.

 Standards promulgated under this chapter shall not be different from federal standards applying to products distributed or used in interstate commerce unless such standards are required by compelling local conditions and do not unduly burden interstate commerce. This provision does not apply to customized products or parts not normally available on the open market, or to optional parts or additions to products which are ordinarily available with such optional parts or additions.

 The provisions of the Iowa administrative procedure Act, chapter 17A, shall apply to judicial review of standards issued under this section. Notwithstanding any provision of the Iowa administrative procedure Act, chapter 17A, to the contrary, a person who is aggrieved or adversely affected by a standard issued under this section must seek judicial review of such standard prior to the sixtieth day after such standard becomes effective. All determinations of the commissioner shall be conclusive if supported by substantial evidence in the record as a whole.

 A railway corporation within the state shall provide adequate sanitation and shelter for all railway employees. The commissioner shall adopt rules requiring railway corporations within the state to provide a safe and healthy workplace. The commissioner shall enforce the requirements of this subsection upon the receipt of a written complaint.