X30 Exposure to excessive natural heat

Not billable (header)Chapter 20

This code needs a 7th character (use X as a placeholder for missing characters).

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Codes under this one

X30.XXXA Exposure to excessive natural heat, initial encounter
X30.XXXD Exposure to excessive natural heat, subsequent encounter
X30.XXXS Exposure to excessive natural heat, sequela

Instructional notes

Chapter 20

Notes

This chapter permits the classification of environmental events and circumstances as the cause of injury, and other adverse effects. Where a code from this section is applicable, it is intended that it shall be used secondary to a code from another chapter of the Classification indicating the nature of the condition. Most often, the condition will be classifiable to Chapter 19, Injury, poisoning and certain other consequences of external causes (S00-T88). Other conditions that may be stated to be due to external causes are classified in Chapters I to XVIII. For these conditions, codes from Chapter 20 should be used to provide additional information as to the cause of the condition.

This code

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.

excessive heat of man-made origin (W92)
exposure to man-made radiation (W89)
exposure to sunlight (X32)
exposure to tanning bed (W89)

Inclusion terms

Exposure to excessive heat as the cause of sunstroke
Exposure to heat NOS

7th charactersThe appropriate 7th character is to be added to code X30

A initial encounter
D subsequent encounter
S sequela

Chapter 20: External causes of morbidity · V00-X58 Accidents (V00-X58)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.