OSHA requires that persons who erect, dismantle, move, or inspect scaffolds be trained by a competent person to recognize hazards. This training must be:

解析

Retraining is owed when changes at the worksite or in the type of scaffold present a hazard the employee has not been trained for, and when the employee's work shows inadequate retention or understanding of the training. An annual cycle (b) is a sensible habit but is neither required nor sufficient: a scaffold type that changes in March cannot wait for next year's class, and a proficient worker needs no calendar refresher. A supplier's certificate (c) speaks to the equipment, not to this employee on this site. And the duty runs to everyone who erects, dismantles, moves, operates, repairs, maintains or inspects a scaffold - not only to the competent person supervising them (d).