Did you realize that OSHA recognizes THREE ascending levels of skill when it come to Work at Height? While it is easy to authorize a worker to perform work where fall hazards exist, you must also ensure more highly trained/knowledgeable persons are also present, or able to supervise:

AUTHORIZED – a worker the employer assigns to perform a specific type of duty or may be in a specific location of an area in the workplace. The work authorized employee performs in situations where fall hazards are present.
COMPETENT PERSON means an individual who, through training and knowledge, is capable of identifying, evaluating and addressing existing and potential fall hazards, and who has the authority to take prompt corrective action about such hazards. Competent persons are responsible for supervising the selection and use of structural anchorage and fall protection system components, conducting inspections before each use, and immediately removing damaged equipment from service.
QUALIFIED – a person who by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated the ability to solve or resolve problems related to the subject, the work, or the project.