Iowa Code § 147.36: Rules.

Each board may establish rules for any of the following:

1. The qualifications required for applicants seeking to take examinations.

2. The denial of applicants seeking to take examinations.

3. The conducting of examinations.

4. The grading of examinations and passing upon the technical qualifications of applicants, as shown by such examinations.

5. The minimum scores required for passing standardized examinations.