X30Exposure to excessive natural heat

X30 is the ICD-10-CM diagnosis code for exposure to excessive natural heat. It belongs to block X30-X39 (exposure to forces of nature) 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.

To report this condition, pick the subcode that matches the documentation: X30.XXXA (initial encounter), X30.XXXD (subsequent encounter) and X30.XXXS (sequela).

Don't report X30 together with the conditions in its Excludes1 note: excessive heat of man-made origin (W92), exposure to man-made radiation (W89), exposure to sunlight (X32) and exposure to tanning bed (W89).

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