Z77.123
Contact with and (suspected) exposure to radon and other naturally occurring radiation
Z77.123 (also written Z77123) is a billable ICD-10-CM diagnosis code for contact with and (suspected) exposure to radon and other naturally occurring radiation. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 31 codes in category Z77 (Other contact with and (suspected) exposures hazardous to health). The Alphabetic Index lists it under 4 entries. Its coding notes include a Code also instruction and 9 Excludes2 entries.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Contact and exposure codes can be first-listed to explain an encounter for testing, or more commonly are secondary codes identifying a potential risk.
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
Also from chapter/block level (1 note)
- any follow-up examination (Z08-Z09)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
- 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)
Includes
Further defines or gives examples of the content of the category.
- contact with and (suspected) exposures to potential hazards to health
Notes
Also from chapter/block level (3 notes)
- 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.
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 4 entries