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ICD-10-CM tabular list

W85-W99Exposure to electric current, radiation and extreme ambient air temperature and pressure

ICD-10-CM codes W85-W99 cover exposure to electric current, radiation and extreme ambient air temperature and pressure, within external causes of morbidity. The block holds 143 codes across 9 categories, of which 99 are billable and 44 are header codes that cannot be submitted on a claim. 143 of them (100%) require a 7th character.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • exposure to:
  • failure in dosage of radiation or temperature during surgical and medical care (Y63.2-Y63.5)
  • lightning (T75.0-)
  • natural cold (X31)
  • natural heat (X30)
  • natural radiation NOS (X39)
  • radiological procedure and radiotherapy (Y84.2)
  • sunlight (X32)

The 7th character in W85-W99

A code in this block is not complete without its 7th character, and a missing one is a rejected claim rather than a denied one: the clearinghouse never passes it on. 143 of the 143 codes here take one.

A
initial encounter
D
subsequent encounter
S
sequela

Categories in W85-W99

ICD-10-CMFY2026-Apr· effective April 1, 2026