32 nurses randomly assigned to the experimental group will receive breathing exercise training. Pre-test and post-test will be conducted to measure compassion fatigue and job stress.

32 nurses randomly assigned to the control group will not receive breathing exercise training. Pre-test and post-test will be conducted to measure compassion fatigue and job stress.

Participants in the experimental group will receive training on proper breathing techniques and breathing exercise methods. Each session will last 30-40 minutes. Sessions will be conducted twice a week for a total of 4 weeks.

The level of compassion fatigue among emergency department nurses will be assessed using the Compassion Fatigue Scale, a Likert-type instrument ranging from 1 ("Never") to 10 ("Very Often"). The scale includes two subdimensions: secondary traumatic stress and occupational burnout. Items C, E, H, K, and L assess secondary traumatic stress, while items A, B, D, F, G, I, and M assess occupational burnout.

Total scores range from 13 to 130, with higher scores indicating greater levels of compassion fatigue.

Work-related stress among emergency nurses will be measured with the 34-item Nurse Work Stress Scale . The scale has seven subdimensions: uncertainty concerning treatment (items 1-8), workload (items 9-14), patient death (items 15-19), conflict with physicians (items 20-24), conflict with other nurses (items 25-29), inadequate support (items 30-32), and suffering patient (items 33-34). Items are scored on a 4-point Likert scale (1=Never, 2=Sometimes, 3=Often, 4=Very Often). Subdimension reliability ranges from α=0.65 to α=0.89. Total scores are summed; higher scores indicate higher work-related stress.