What type of injuries are considered excluded from employee claims under WC?

Injuries caused solely by mental health issues are considered excluded from employee claims under Workers' Compensation (WC) because WC systems generally emphasize physical injuries resulting from workplace accidents or hazards. While psychological conditions can arise from work-related stress or trauma, for the claims to be compensable, they typically need to be tied to a physical injury or a clear work-related event. This distinction is important in WC claims since the system is designed primarily for physical injuries that can be directly linked to job duties or environment.

The other options involve various scenarios that may still qualify as compensable under certain circumstances. The absence of a witness does not negate the validity of an injury claim. Similarly, injuries sustained in vehicular accidents can be compensable if they occur within the scope of employment or while performing job duties. Lastly, injuries that happen during break periods may still be covered, especially if the breaks are considered part of work activities. Therefore, the focus on solely mental health conditions as a reason for exclusion aligns with how WC regulations typically delineate between physical and psychological claims.