ICDcodes.org
FY2027

T31 vs T66

T31 and T66 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.

The official note, declared on T66
burns (T20-T31)
T31

Burns classified according to extent of body surface involved

Not billable
Chapter 19
Injury, poisoning and certain other consequences of external causes
Section
T30-T32
T66

Radiation sickness, unspecified

Not billable
Chapter 19
Injury, poisoning and certain other consequences of external causes
Section
T66-T78
Indexed under
  • Irradiation effects, adverse
  • Effect, adverse › infraredNOS
  • Effect, adverse › radiationNOS
  • Effect, adverse › ultravioletNOS
  • Radiation › effects NOS

Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027