What 29 CFR 1926.1427 requires (plain English)
29 CFR 1926.1427 sets the operator qualification and certification requirements of Subpart CC, OSHA's construction cranes and derricks standard. After a 2018 revision, it requires that before operating equipment covered by the subpart, an operator be trained, certified or licensed, and evaluated by the employer.
Certification can come from an accredited testing organization, an audited employer program, a qualifying U.S. military program, or a state or local license that meets OSHA's criteria. But certification demonstrates general knowledge and skill, not competence on a specific machine and task. So the employer must separately evaluate each operator's ability to safely operate the particular equipment, including its configuration and the work to be performed, and document that evaluation.
1926.1427 is part of the Subpart CC framework scoped by 1926.1400, alongside power-line safety (1926.1408), keeping clear of loads (1926.1425), signal-person and rigger qualification, and assembly/disassembly. Operator qualification is the human-competence pillar of safe crane operation.