X37.41XA
Tidal wave due to earthquake or volcanic eruption, initial encounter
X37.41XA (also written X3741XA) is a billable ICD-10-CM diagnosis code for tidal wave due to earthquake or volcanic eruption, initial encounter. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 27 codes in category X37 (Cataclysmic storm). Its 7th character, A, means initial encounter.
7th character
Category X37 requires a 7th character. X37.41 has only 5 characters, so a placeholder X fills the 6th position.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
An external cause code is never a principal or first-listed diagnosis. Its 7th character is assigned for each encounter and should match the injury or condition code.
Inclusion terms
Conditions classified to this code.
- Tidal wave NOS
- Tsunami
Notes
Also from chapter/block level (1 note)
- 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.