Sign in →

Specific Gravity

Performing Laboratory

Barnes-Jewish Hospital Laboratory

Methodology

Method Name:

Specific gravity: Refractometry

Literature References:

  • Brunzel, N. A.: Fundamentals of Urine and Body Fluid Analysis, 4th ed., St. Louis, MO; Elsevier; 2018; pp. 68-210.

Specimen Requirements

Specimen Type: Urine, random

Container/Tube: Yellow/red-top UA preservative tube

Specimen Volume: Full tube

Specimen Minimum Volume: 5 mL 

Collection Instructions:

1. Collect a midstream voided specimen.Urine Collection

3. Using cannula in collection cup lid, fill yellow-top, plastic, conical tube.

Additional Information:

1. Label tube with patient’s name and date of birth.

2. A catheterized specimen is acceptable.

3. Provide collection date and time, and method of collection.

4. If storage and transport is >1 hour, refrigerate specimen.

5. Specimen should be received in the laboratory within 2 hours of collection.

Day(s) Test Set Up

Monday through Sunday, 24 hours / 7 days a week

Turnaround Time:

Urinalysis: STAT: 1 hour after receipt in laboratory

Routine: 2-4 hours after receipt in laboratory

 

Test Classification and CPT Coding

81003-Specific gravity

 

Reference Values

Specific gravity: 1.003-1.030
 

Specimen Transport Temperature

Ambient <1 hour

Refrigerate >1 hour

Additional Information

For BJH Laboratory Use Only

Alternate Tube(s):

1 Yellow top urine tube

Analyte Stability:

Specimen should be received in the laboratory within 2 hours of collection. However, using a UA Preservative tube extends the stability

Laboratory Processing Instructions:

If specimen is received in a cup, lab processing personnel should use the cannula in the lid to transfer the urine to a yellow top tube before transporting to the UA tech.