Final answer:
Counselor impairment is increased by personal and work-related stressors such as trauma, pre-existing conditions, trauma patients, and substance abuse or depression, but not by working with clients who have managed health care plans.
Step-by-step explanation:
Factors that can increase counselors' vulnerability to impairment include trauma, pre-existing conditions, dealing with trauma patients, and personal issues like substance abuse or depression. These factors can lead to burnout, depression, and other forms of professional impairment. However, working with a significant number of clients who have managed health care plans is not typically associated with increasing vulnerability to impairment among counselors. Rather, it's factors like job strain, unhealthy lifestyles, dangerous working conditions, and lack of support that contribute to the risk.