2026 ICD-10-CM Diagnosis Code W99Exposure to other man-made environmental factors
W99 is a non-billable ICD-10-CM category code for exposure to other man-made environmental factors, so it cannot be submitted on claims. Use a more specific code from this category instead, such as W99.XXXA, W99.XXXD, and W99.XXXS.
Code Identity
Code Classification
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
7th Character Note
- The appropriate 7th character is to be added to code W99
7th Character
- A - initial encounter
- D - subsequent encounter
- S - sequela
Certain ICD-10-CM categories have applicable 7th characters. The applicable 7th character is required for all codes within the category, or as the notes in the Tabular List instruct. The 7th character must always be the 7th character in the data field. If a code that requires a 7th character is not 6 characters, a placeholder X must be used to fill in the empty characters.
Indicates that a seventh character is to be assigned to codes in a subcategory.
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index; each main term links to its index entry.
Code HistoryHistory
Questions About W99Overview
What is the ICD-10 code for exposure to other man-made environmental factors?
W99 is the ICD-10-CM category for exposure to other man-made environmental factors, but it is a non-billable header: claims need a more specific code from this category, listed on this page.
Is W99 (Exposure to other man-made environmental factors) a billable code?
No. This is a category header that groups the codes for exposure to other man-made environmental factors, and headers cannot be submitted on claims. Claims for exposure to other man-made environmental factors need a more specific code from this category, such as W99.XXXA, W99.XXXD, and W99.XXXS.
