LOINCActiveObservation

LOINC Code 94658-2: City of known exposure

94658-2 is a LOINC code used to identify City of known exposure in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component City of known exposure. It is commonly used with the system or sample type ^Patient.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component City of known exposure. It is commonly used with the system or sample type ^Patient.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Observation

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • City of known exposure
  • City of exposure; Exp; H+P; H+P.HX; Location; Nominal; P prime; Point in time; Random

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

City of known exposureCity of exposureH&P.HXLocPt^PatientNom

Frequently asked questions

Code details

Code94658-2
SystemLOINC
Display nameCity of known exposure
Short nameCity of exposure
ComponentCity of known exposure
PropertyLoc
TimingPt
System (specimen)^Patient
ScaleNom
ClassH&P.HX
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.68
Last changed2.68

Part names

City of known exposureLocPt^PatientNomLocationPoint in time (spot)

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.