W31.1 – Contact with metalworking machines

ICD-10-CM 2027 diagnosis code · Exposure to inanimate mechanical forces

Non-billable header

ICD-10-CM code W31.1

Code: W31.1 (claims format: W311)
Description: Contact with metalworking machines
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 20. External causes of morbidity (V00-Y99)
Block: W20-W49 Exposure to inanimate mechanical forces
Parent codes: W31

Billable codes under W31.1

W31.1 is a header code and cannot be used on claims. Choose the most specific code:

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care (use placeholder X for empty positions).

Character	Meaning
`A`	initial encounter
`D`	subsequent encounter
`S`	sequela

Notes for W31.1

Applicable to:

Contact with abrasive wheel
Contact with forging machine
Contact with lathe
Contact with mechanical shears
Contact with metal drilling machine
Contact with milling machine
Contact with power press
Contact with rolling-mill
Contact with metal sawing machine

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

W31 – Contact with other and unspecified machinery

Excludes1 (not coded here):

contact with agricultural machinery (W30.-)
contact with machinery in transport under own power or being towed by a vehicle (V01-V99)
exposure to electric current (W86)

7th character note:

The appropriate 7th character is to be added to each code from category W31

Block W20-W49

Excludes1 (not coded here):

assault (X92-Y09)
contact or collision with animals or persons (W50-W64)
exposure to inanimate mechanical forces involving military or war operations (Y36.-, Y37.-)
intentional self-harm (X71-X83)

Related codes in W31

Frequently asked questions

What is ICD-10 code W31.1?

W31.1 is the ICD-10-CM code for contact with metalworking machines, in the block W20-W49 (Exposure to inanimate mechanical forces).

Is W31.1 a billable code?

No. W31.1 is a header code with more specific child codes; report one of the billable codes listed above.

What category does W31.1 belong to?

It belongs to category W31 – Contact with other and unspecified machinery.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.