Fecal Occult Blood (FOB) cards are diagnostic specimens used to detect hidden blood in stool samples, a common component of routine colorectal screening programs. These cards contain patient material and are transported from collection sites to laboratories for analysis. Because they contain human biological material, the process of shipping them is strictly governed by hazardous materials regulations designed to protect public health and transport workers. Correctly classifying the specimen is necessary for compliance, as improper classification or packaging can result in significant fines and present a safety risk during transit.
The Regulatory Framework for Diagnostic Specimens
The shipment of biological materials is regulated globally by organizations like the International Air Transport Association (IATA) and domestically by the Department of Transportation (DOT) under 49 CFR. These regulations establish a tiered classification system for infectious substances based on the risk posed during transportation. This framework dictates the necessary packaging, labeling, and documentation required.
The highest risk tier is Category A (UN 2814 or UN 2900), reserved for infectious substances capable of causing permanent disability, life-threatening, or fatal disease. This category requires the most stringent packaging and is rarely applied to routine diagnostic samples. Category B (UN 3373) is a more common classification, applying to infectious substances that do not meet the criteria for Category A, representing a moderate to low risk.
A third, less-regulated tier is the Exempt Human Specimen classification, applied to samples where there is a minimal likelihood that pathogens are present. This designation is commonly used for routine clinical samples like those for cholesterol or hormone levels. The determination of which category applies is the responsibility of the shipper, who must rely on patient history and the purpose of the test.
Determining the Specific Classification
Fecal Occult Blood cards are explicitly mentioned in dangerous goods regulations as typically qualifying for the Exempt Human Specimen classification. Since the FOB test is a routine screening tool, not a diagnostic test for a known infectious disease, the biological material carries a minimal risk of containing dangerous pathogens. This low-risk profile allows the shipment to bypass the complex requirements of the UN 3373 classification.
To qualify as Exempt, the sample must be collected for routine screening or diagnosis of a non-infectious condition, such as detecting blood that may indicate polyps or cancer. If the patient has a known or suspected infectious disease that meets the Category A criteria, the FOB card must be shipped as a Category A infectious substance. The Exempt classification is intended for instances where the shipper has no reasonable basis to suspect the presence of a dangerous pathogen.
If the FOB card does not qualify for the Exempt Human Specimen status, it must default to the Biological Substance, Category B (UN 3373) classification. This occurs if the laboratory or carrier has a policy requiring the higher classification for all human specimens, or if the shipper cannot confirm the minimal risk criteria. The ultimate decision rests on the shipper’s professional judgment regarding the probability of infectious material being present.
Essential Shipping and Packaging Requirements
Triple Packaging System
Regardless of whether the FOB card is classified as Exempt Human Specimen or UN 3373, the packaging must utilize a protective Triple Packaging system. This system consists of three independent components. The specimen is placed in a leak-proof primary receptacle, which is then secured within a secondary packaging container.
The secondary container must hold sufficient absorbent material to soak up the entire volume of liquid from the primary receptacle should it leak. Both internal components are placed within a rigid outer packaging that provides physical protection during transit. For UN 3373 shipments, the secondary packaging must be capable of withstanding a 95kPa pressure differential, and the completed package must pass a 1.2-meter drop test.
Labeling and Marking Requirements
Specific labeling and marking requirements are dictated by the final classification. A package classified as UN 3373 must display the diamond-shaped UN 3373 label and the proper shipping name, “Biological Substance, Category B.” Conversely, packages shipped as Exempt Human Specimen must be clearly marked with the phrase “Exempt Human Specimen” and do not require the UN 3373 diamond.
Training and Documentation
All personnel involved in preparing these biological shipments for transport must complete mandatory training that meets IATA and DOT requirements. This training ensures the shipper understands the classification criteria, packaging instructions, and required documentation, such as the waybill or manifest. The shipper is responsible for retaining all associated shipping documentation for a minimum period, often two years, to maintain compliance records.