W94 – Exposure to high and low air pressure and changes in air pressure

ICD-10-CM 2027 diagnosis code · Exposure to electric current, radiation and extreme ambient air temperature and pressure

Non-billable header

ICD-10-CM code W94

Code: W94 (claims format: W94)
Description: Exposure to high and low air pressure and changes in air pressure
Short description: Expsr to high and low air pressr and changes in air pressure
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: W85-W99 Exposure to electric current, radiation and extreme ambient air temperature and pressure

Billable codes under W94

W94 is a header code and cannot be used on claims. Choose the most specific code:

W94.0 – Exposure to prolonged high air pressureHeader (more codes below)
W94.1 – Exposure to prolonged low air pressureHeader (more codes below)
W94.2 – Exposure to rapid changes in air pressure during ascentHeader (more codes below)
W94.3 – Exposure to rapid changes in air pressure during descentHeader (more codes below)

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 W94

7th character note:

The appropriate 7th character is to be added to each code from category W94

Notes inherited from parent codes

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

Block W85-W99

Excludes1 (not coded here):

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)

Frequently asked questions

What is ICD-10 code W94?

W94 is the ICD-10-CM code for exposure to high and low air pressure and changes in air pressure, in the block W85-W99 (Exposure to electric current, radiation and extreme ambient air temperature and pressure).

Is W94 a billable code?

No. W94 is a header code with more specific child codes; report one of the billable codes listed above.

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.