2027 ICD-10-CM Diagnosis Code Z77.4Contact with and (suspected) exposure to blast overpressure

ICD-10-CM Codes›Z00–Z99›Z77-Z99›suspected

ICD-10-CM Z77.4
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Z77.4 is a non-billable ICD-10-CM category code for contact with and (suspected) exposure to blast overpressure, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Z77.40, Z77.41, Z77.42, and Z77.49.

Code Identity

ICD-10-CM Code
Z77.4
Billable Status
No — Non-Billable Category
Code Describes
Contact with and (suspected) exposure to blast overpressure
Short Description
Contact with and (suspected) exposure to blast overpressure
Same as the full description in the CMS dataset.
Parent Code
Z77
Other contact with and (suspected) exposures hazardous to health

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ77-Z99Persons with potential health hazards related to family and personal history and certain conditions influencing health status
CategorysuspectedOther contact with and exposures hazardous to health (Z77)
This CodeZ77.4Contact with and (suspected) exposure to blast overpressure

Specific Coding for Contact with and (suspected) exposure to blast overpressureOverview

Non-specific codes like Z77.4 require more characters. Use one of these billable codes instead:

  • Use Z77.40 for Contact with and (suspected) exposure to unspecified blast overpressure

  • Use Z77.41 for Contact with and (suspected) exposure to low-level blast overpressure

  • Use Z77.42 for Contact with and (suspected) exposure to high-level blast overpressure

  • Use Z77.49 for Contact with and (suspected) exposure to other blast overpressure

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Z77.4: its own notes plus those printed at Z77, block Z77-Z99, and Chapter 21. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Z77 Other contact with and (suspected) exposures hazardous to health applies to 31 codes
  • contact with and (suspected) exposures to potential hazards to health

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Z77 Other contact with and (suspected) exposures hazardous to health applies to 31 codes
  • contact with and (suspected) exposure to communicable diseases (Z20.-)
  • exposure to (parental) (environmental) tobacco smoke in the perinatal period (P96.81)
  • newborn affected by noxious substances transmitted via placenta or breast milk (P04.-)
  • occupational exposure to risk factors (Z57.-)
  • retained foreign body (Z18.-)
  • retained foreign body fully removed (Z87.821)
  • toxic effects of substances chiefly nonmedicinal as to source (T51-T65)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From Block Z77-Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status applies to 567 codes
  • any follow-up examination (Z08-Z09)

Notes

General instructions on how these codes are used.

From Chapter 21 (Z00-Z99) Factors influencing health status and contact with health services applies to 1,425 codes
  • Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
  • (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
  • (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Z77.4, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming Z77.4: they are not reported together with it, unless the two conditions are unrelated.

  • Block T51-T65 Toxic effects of substances chiefly nonmedicinal as to source
    contact with and (suspected) exposure to toxic substances (Z77.-) names Z77.-, which includes this code
  • Z03 Encounter for medical observation for suspected diseases and conditions ruled out
    contact with and (suspected) exposures hazardous to health (Z77.-) names Z77.-, which includes this code
  • Z13.88 Encounter for screening for disorder due to exposure to contaminants
    those exposed to contaminants without suspected disorders (Z57.-, Z77.-) names Z77.-, which includes this code

Excludes2 2

These codes carry an Excludes2 note naming Z77.4: its condition is not part of those codes, and both may be reported when the patient has both.

  • P04 Newborn affected by noxious substances transmitted via placenta or breast milk
    newborn in contact with and (suspected) exposures hazardous to health not transmitted via placenta or breast milk (Z77.-) names Z77.-, which includes this code
  • Z91 Personal risk factors, not elsewhere classified
    contact with and (suspected) exposures hazardous to health (Z77.-) names Z77.-, which includes this code

Code HistoryHistory

FY 2027AddedAdded to the ICD-10-CM code setEffective October 1, 2026.
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Z77.4Overview

What is the ICD-10 code for contact with and (suspected) exposure to blast overpressure?

Z77.4 (sometimes written as Z774) is the ICD-10-CM category for contact with and (suspected) exposure to blast overpressure, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is Z77.4 a billable code?

No. This is a category header that groups the codes for contact with and (suspected) exposure to blast overpressure, and headers cannot be submitted on claims. Claims for contact with and (suspected) exposure to blast overpressure need a more specific code from this category, such as Z77.40, Z77.41, and Z77.42.