ICD-10-CM > V00-Y99 > Y35-Y38 > Y37 > Y37.7 > Y37.7X > Y37.7X1 Y37.7X1 Military operations involving chemical weapons and other forms of unconventional warfare, civilian Non-Billable/Non-Specific Codes Y37.7X1A..., initial encounterY37.7X1D..., subsequent encounterY37.7X1S..., sequela