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ICD-10-CM 2027 diagnosis code

W40.1Explosion of explosive gases

Not billable — use a more specific codeRequires 7th character

W40.1 is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it and add the required 7th character.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About W40.1

W40.1 is the ICD-10-CM diagnosis code for explosion of explosive gases. It belongs to category W40 (explosion of other materials), block W20-W49 (exposure to inanimate mechanical forces) and chapter 20 (external causes of morbidity). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.

Within W40 (explosion of other materials), W40.1 is specifically for explosion of explosive gases. Related codes cover blasting material (W40.0), other specified explosive materials (W40.8) and unspecified explosive materials (W40.9).

Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

7th character

The appropriate 7th character is to be added to each code from category W40

Coding notes

Applicable toConditions and synonyms classified to this code
  • Explosion of acetylene
  • Explosion of butane
  • Explosion of coal gas
  • Explosion in mine NOS
  • Explosion of explosive gas
  • Explosion of fire damp
  • Explosion of gasoline fumes
  • Explosion of methane
  • Explosion of propane

Notes that apply from higher levels

Instructions written at a parent level also apply to W40.1.

› From W40 Explosion of other materials
Excludes1
  • assault by explosive material (X96)
  • explosion involving legal intervention (Y35.1-)
  • explosion involving military or war operations (Y36.0-, Y36.2-)
  • intentional self-harm by explosive material (X75)

Broader instructions also apply from W20-W49 Exposure to inanimate mechanical forces and Chapter 20: External causes of morbidity.

Alphabetic index entries

14 entries

Terms in the official ICD-10-CM index that lead to W40.1.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about W40.1

Is W40.1 billable?

No. W40.1 is a header code. Report one of its more specific subcodes instead.