OSHA's "Focus Four" refers to the four most common causes of severe injury and death in the construction industry: falls, electrocutions, caught-in/between hazards, and struck-by hazards. OSHA provides training and education resources for employers and workers to help prevent these types of accidents.

The "struck-by" hazards specifically refer to accidents where a worker is hit by an object or vehicle. This can include being struck by falling objects, vehicles on the job site, or equipment being operated by another worker.