W34 vs Y37
W34 (Accidental discharge and malfunction from other and unspecified firearms and guns) compared with Y37 (Military operations), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. W34 carries an Excludes1 note covering Y37: “exposure to inanimate mechanical forces involving military or war operations (Y36.-, Y37.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| W34Accidental discharge and malfunction from other and unspecified firearms and guns | Y37Military operations | |
|---|---|---|
| Billing status | Non-billable header Report instead: W34.00XA, W34.00XD, W34.00XS, W34.010A, W34.010D | Non-billable header Report instead: Y37.000A, Y37.000D, Y37.000S, Y37.001A, Y37.001D |
| Classification | V00-Y99 — External Causes of Morbidity (V00-Y99) | V00-Y99 — External Causes of Morbidity (V00-Y99) |
| Definition | Accidental discharge and malfunction from other and unspecified firearms and guns is a non-billable ICD-10-CM category code (W34). | Military operations is a non-billable ICD-10-CM category code (Y37). |
| 7th character | The appropriate 7th character is to be added to each code from category W34 | The appropriate 7th character is to be added to each code from category Y37 |
| Includes | — | injuries to military personnel and civilians occurring during peacetime on military property and during routine military exercises and operations |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources