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Ammonia (NH3)

Tube Type = Green Top

Tube Type
(No GEL)

Must be delivered in lab on ice within 15 minutes of collection.

Test ID LAB47
EPIC Order AMMONIA
CPT Code(s) 82140
Group/Individual Test Individual
Laboratory Core Laboratory
Tube Station Deliver directly to laboratory immediately after collection on ice
Specimen Routine: 3 mL blood/green lithium heparin NO GEL tube (minimum 1mL); See Comments 
Micro: 250 µL blood/green pediatric lithium heparin green tube NO GEL microtainer
Stability
 		 Unspun: 15 minutes on ice; See comments
Spun/Separated,
Refrigerated:		 ≤3 hours (plasma only)

Frozen:

<24 hours (plasma only)

Room Temperature:

N/A
Availability 24 hrs/day
Turnaround Time 1 hour
Reference Range Normal: 11-32 µmol/L
Comments
  • Must be delivered in lab on ice within 15 minutes of collection.
  • Specimens not received on ice will be rejected.
  • Specimens sent in tubes with gel will be rejected.
  • Outreach samples are acceptable if centrifuged within 15 minutes, separated, and the plasma is transferred into a labeled aliquot tube.
  • The sample must be kept on ice during transport to the laboratory. Contact lab for special handling instructions.
  • Sample must be sent to the laboratory STAT.
  • Sodium Heparin is not an acceptable sample type.

Reviewed by J. Carr on November 25, 2025

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514