LOINCActiveObservation

LOINC Code 49495-5: HBV surface Ab actual/Negative control [Rel units/Vol]

49495-5 is a LOINC code used to identify HBV surface Ab actual/Negative control [Rel units/Vol] 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 Hepatitis B virus surface Ab Actual/Negative control. It is commonly used with the system or sample type Ser/Plas.

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 Hepatitis B virus surface Ab Actual/Negative control. It is commonly used with the system or sample type Ser/Plas.

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

  • Hepatitis B virus surface Ab actual/Negative control in Serum or Plasma
  • Hepatitis B virus surface Ab Actual/Negative control
  • Ab S; ABS; Aby; Antby; Anti; Antibodies; Antibody; anti-HBsAg; Autoantibodies; Autoantibody; HBs; HBsAB; HBV; HBV surface; Hep; Hep B; Hep Bs; Hepatis; Hepatit; HepB; ID; Infectious Disease; InfectiousDisease; Microbiology; NEG; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; RlACnc; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; Surf

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

HBV surface Ab actual/Negative control [Rel units/Vol]Hepatitis B virus surface Ab actual/Negative control in Serum or PlasmaHBV surface Ab S SerPlHepatitis B virus surface Ab Actual/Negative controlMICROHepatitis B virus (HBV) Surface/Negative Control, BloodRelACnc

Frequently asked questions

Code details

Code49495-5
SystemLOINC
Display nameHBV surface Ab actual/Negative control [Rel units/Vol]
DescriptionHepatitis B virus surface Ab Actual/Negative control
Short nameHBV surface Ab S SerPl
ComponentHepatitis B virus surface Ab Actual/Negative control
PropertyRelACnc
TimingPt
System (specimen)Ser/Plas
ScaleQn
ClassMICRO
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.22
Last changed2.68

Consumer names

Hepatitis B virus (HBV) Surface/Negative Control, Blood

Part names

Hepatitis B virus surface Ab Actual/Negative controlRelACncPtSer/PlasQnRelative Arbitrary ConcentrationPoint in time (spot)Serum or Plasma

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.

LOINC Code 49495-5 | HealthAssure