T52.811 vs Z77
T52.811 (Toxic effect of alkenes, accidental (unintentional)) compared with Z77 (Other contact with and (suspected) exposures hazardous to health), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. T52.811 carries an Excludes1 note covering Z77: “contact with and (suspected) exposure to toxic substances (Z77.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| T52.811Toxic effect of alkenes, accidental (unintentional) | Z77Other contact with and (suspected) exposures hazardous to health | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | Z00-Z99 — Factors Influencing Health Status and Contact with Health Services (Z00-Z99) |
| Definition | — | Other contact with and (suspected) exposures hazardous to health is a non-billable ICD-10-CM category code (Z77). |
| 7th character | The appropriate 7th character is to be added to each code from category T52 | — |
| Includes | Toxic effects of alkenes NOS | contact with and (suspected) exposures to potential hazards to health |
| Use additional code | code(s): for all associated manifestations of toxic effect, such as: respiratory conditions due to external agents (J60-J70) personal history of foreign body fully removed (Z87.821) | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources