Test Code BF37 Specific Gravity, Urine
Clinical Information
Specific gravity is defined as the ratio of the mass of the urine to the mass of an equal volume of water, and is an indicator of the kidneys' ability to concentrate or dilute the urine.
Synonym
- USG
Specimen Required
Preferred Container/Tube: Urine Container
Acceptable Container/Tube: Urine Container
Specimen Volume: 8 mL
Specimen Minimum Volume: 5 mL
Specimen Stability Information
Ambient:
Non-preservative tubes: 2 hours
Preservative tubes: 72 hours
NOTE: Preservative specimens are accepted but are not recommended.
Refrigerated: 8 hours
Rejected Due To
- Unlabeled specimens
- Ambient specimens >2 hours old
- Specimens with fecal or vaginal contamination
- Use of boric acid urine preservative
- Specimens in collection cups
Reference Values
1.001-1.035
Method Description
Clinical Lab UH: Fiber optic refractive index method.
Clinical Lab University East: Fiber optic refractive index method.
Clinical Lab James: Fiber optic refractive index method.
All Performing Labs: pKa change of pretreated polyelectrolyte in relation to ionic concentration.
Performing Lab
Clinical Lab UH
Clinical Lab University East
Clinical Lab James
Clinical Lab Martha Morehouse
Clinical Lab Spielman
Clinical Lab West Campus
Day(s) Performed
Monday through Sunday
Report Available
Same day/1 day
Reporting Name
Specific Gravity, Urine
CPT Code Information
81003
LOINC Code Information
2965-2