Specimen Storage

Specimen Storage Guidelines

Critical Frozen Specimens
Serum or plasma aliquots indicated as critical frozen must remain frozen until thawed for testing. Repeat thaw and refreezing of samples is unacceptable. Please note that multiple tests cannot be performed on a critical frozen test indication. Separate samples must be submitted for each test.

Light
Exposing a specimen to light causes a breakdown of some analytes such as bilirubin. Keep all specimens away from bright light. Some tests require specimens be wrapped in aluminum foil or be kept in a paper bag to prevent exposure to light.

Temperature Requirements
Specimen bags should be clearly marked to indicate the temperature at which the specimen needs to be maintained.

General Recommendations:
Room Temperature:  18-26°C (64-79°F)
Refrigerate: 2-8°C (36-46°F)
Freeze: -15°C or colder (5°F or colder)
Dry Ice: -70°C (-94°F)

Please refer to the Test Table section for individual test requirements.

Whole Blood
Whole blood specimens should be collected in the designated anticoagulant tube. Gently invert the tube eight (8) times immediately after collection to evenly distribute the additive. Deliver to the laboratory as soon as possible after collection and follow temperature and storage guidelines indicated for the specific test.

Stool Collection
A special stool collection system for Ova & Parasites (O&P) and stool culture is available by calling 503-413-1234 or Toll Free 877-270-5566. Carefully follow the instructions in the kit.

Timed stool collections should be collected in a clean dry container with a tight lid. Submit an aliquot of the sample. Minimum acceptable sample is 20 grams. Volume samples should be preweighed and aliquoted at your location if possible. Send entire collection if this process cannot be performed. See Stool Specimen Collection Guidelines 24 Hours for how to collect a timed stool collection. Indicate hours of collection and total weight, if appropriate, on the test requisition.