Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Code Set: New for FY2027 — not valid before October 1, 2026.

Official Registry Overview & Definition

No additional overview provided for this record.

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for Z77.42 in the official ICD-10-CM tabular list.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

contact with and (suspected) exposures to potential hazards to health

Inclusion Terms

Alternative terms the tabular list files under this code.

Contact with and (suspected) exposure to HLB overpressure

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

contact with and (suspected) exposure to communicable diseases (Z20.-) Compare Z77.42 vs Z20 →
exposure to (parental) (environmental) tobacco smoke in the perinatal period (P96.81) Compare Z77.42 vs P96.81 →
newborn affected by noxious substances transmitted via placenta or breast milk (P04.-) Compare Z77.42 vs P04 →
occupational exposure to risk factors (Z57.-) Compare Z77.42 vs Z57 →
retained foreign body (Z18.-) Compare Z77.42 vs Z18 →
retained foreign body fully removed (Z87.821) Compare Z77.42 vs Z87.821 →
toxic effects of substances chiefly nonmedicinal as to source (T51-T65) Compare Z77.42 vs T51 →

Code Also

Additional codes that may be required to fully describe the encounter.

any follow-up examination (Z08-Z09)

Change history

FY2027 — 2026-10-01
Added to the code set
Contact with and (suspected) exposure to high-level blast overpressure
FY2027 changes

Verify Before Coding

Billable — reportable as written.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.

Referenced by Other Codes

Official ICD-10-CM tabular notes on other codes that name Z77.42 or its code family.

18 Excludes1 notes across 2 chapters: T51 (via Z77.-), T51-T65 (via Z77.-), T52 (via Z77.-), T53 (via Z77.-), T54 (via Z77.-), T55 (via Z77.-), T56 (via Z77.-), T57 (via Z77.-), T58 (via Z77.-), T59 (via Z77.-) and 8 more.

2 Excludes2 notes across 2 chapters: P04 (via Z77.-), Z91 (via Z77.-).

Nearest Codes in This Family

Official ICD-10-CM classifications closest to Z77.42 in its code family, with their registry titles.

Z77.29 — Contact with and (suspected) exposure to other hazardous substances
Z77.3 — Contact with and (suspected) exposure to war theater
Z77.31 — Contact with and (suspected) exposure to Gulf War theater
Z77.32 — Contact with and (suspected) exposure to burn pits in war theater
Z77.33 — Contact with and (suspected) exposure to Agent Orange
Z77.39 — Contact with and (suspected) exposure to other war theater
Z77.4 — Contact with and (suspected) exposure to blast overpressure
Z77.40 — Contact with and (suspected) exposure to unspecified blast overpressure
Z77.41 — Contact with and (suspected) exposure to low-level blast overpressure
Z77.49 — Contact with and (suspected) exposure to other blast overpressure

View all codes in the Z77 family

Indexed Clinical Terms (2)

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.

Contact (with), blast overpressure NOS, high-level (HLB)
Exposure (to), blast overpressure NOS, high-level (HLB)

Z77.42 ICD-10-CM Code: Contact with and (suspected) exposure to high-level blast overpressure