Shipping a biological sample across a border is not one compliance task, it is five stacked on top of each other: classifying the material correctly, packaging it to a specific engineering standard, obtaining the right import and export permits, filing accurate customs paperwork, and using carriers and staff who are certified to handle it. Miss any one layer and a shipment gets refused at a courier depot, held at customs, or — worse — released without the containment it needed. This guide walks through the workflow in order and links out to CASRAI’s dedicated guides for the pieces that deserve their own depth.
This page focuses on the parts of international biological-sample shipping that a single classification or packaging guide does not cover on its own: the sequencing of the five layers, and the permit and customs steps that specifically apply once a shipment crosses a border rather than moving lab-to-lab within one country.
Step 1: Classify the material before you do anything else
Everything downstream — packaging, paperwork, and which permits apply — depends on how the material is classified under the UN Model Regulations that IATA, ICAO, and most national dangerous-goods rules are built on. Infectious substances affecting humans or animals are split into two regulatory tiers:
- Category A (UN 2814 / UN 2900) — capable of causing permanent disability or life-threatening/fatal disease in otherwise healthy humans or animals when exposure occurs. Subject to the most stringent packaging, marking, and shipper’s-declaration requirements.
- Category B (UN 3373) — an infectious substance that does not meet the Category A criteria. This covers the large majority of routine diagnostic and research specimens.
Many biological samples — patient specimens with a low likelihood of containing a pathogen, environmental samples, or materials that have been rendered non-infectious (fixed, inactivated, or otherwise treated) — may be exempt from the infectious-substance rules entirely, though they can still trigger other requirements (dry ice, genetically modified organism rules, or agricultural/wildlife import controls). Classification is a judgment call made against defined criteria, not a guess, and it is the one step every later step depends on getting right. See CASRAI’s dedicated guide for the full decision criteria: Shipping Biological Substances by Air: Category A vs. Category B Classification Explained.
Step 2: Package to the standard your classification requires
Category A and Category B substances are packaged under different IATA Packing Instructions (commonly cited as PI 620 for Category A and PI 650 for Category B), both built on the same underlying concept: triple packaging. A leak-proof primary receptacle holding the sample sits inside a secondary packaging (also leak-proof, with enough absorbent material to contain the entire contents if the primary receptacle fails), which sits inside a rigid outer packaging that carries the required markings and, for Category A, UN performance-tested certification.
Most biological shipments also travel on dry ice (UN 1845, Class 9) to maintain a frozen cold chain, which adds its own classification, quantity-limit, and package-marking requirements on top of the infectious-substance rules — the two hazard classes are handled together in the same shipment but regulated separately. If refrigerated rather than frozen transport is needed, temperature-band and excursion-monitoring requirements apply instead. For the packaging mechanics in depth, see:
- Dry Ice Shipping Regulations: UN1845, Class 9, and Packing Instruction 954
- Cold-Chain Shipping Requirements for Biological Reagents: Temperature Ranges, Packaging, and Documentation
- IATA Dangerous Goods Regulations: A Lab Shipper’s Guide
Step 3: Confirm which import and export permits apply
This is the step that is genuinely specific to crossing a border, and it is the one most often missed by labs used to shipping domestically. Depending on the material and the origin/destination countries, one or more of the following may need to be secured before the shipment moves — permit processing routinely takes weeks, not days, so this belongs at the start of planning, not the end:
- Destination-country import permit for infectious/biological materials. In the United States, importation of infectious biological agents, infectious substances, and vectors is regulated under CDC’s Import Permit Program (commonly cited to 42 CFR 71.54); many other national public-health authorities run an equivalent program. The importer, not the shipper, typically holds this permit, and it must generally be in hand before the material ships.
- Agricultural and biosafety permits. Material that could carry a plant pest, animal pathogen, soil, or other regulated agricultural component may require a separate permit from the destination country’s agricultural authority (in the US, USDA APHIS) independent of any infectious-substance permit.
- Wildlife- or endangered-species-derived material. Samples derived from CITES-listed species require CITES export and import permits regardless of infectious status.
- The underlying legal right to send and receive the material. A permit gets material through a border; it doesn’t establish who owns it, who can use it, or for what. That’s the role of a Material Transfer Agreement — see Material Transfer Agreements (MTA): The Practical Process for Sharing Research Materials. Get the MTA (and any required IRB/ethics or biobank consent scope) settled before requesting import permits, since permit applications often ask for it.
Permit requirements vary by country, by material type, and by whether human, animal, or plant pathogens are involved — there is no single universal checklist. Confirm current requirements directly with the destination country’s public-health and agricultural authorities (and, for US-origin shipments, with your institution’s export-control office) before relying on a general description like this one.
Step 4: Prepare accurate customs documentation
Customs clearance runs on paperwork accuracy, not on the underlying compliance work being correct. A shipment can be perfectly classified, packaged, and permitted and still get held at a border because the customs paperwork doesn’t match. Expect to prepare:
- A commercial or pro forma invoice with an accurate material description (avoid vague terms like “samples” or “specimens” alone — customs officers look for a description specific enough to assess), a declared value (even for no-commercial-value research material, most customs authorities require a nominal declared value and a “not for resale, no commercial value” statement), quantity, and the correct tariff/HS classification.
- A Dangerous Goods Declaration (Shipper’s Declaration) for any Category A infectious substance or other regulated dangerous good in the shipment, prepared by DOT/IATA-certified personnel.
- Copies of the import/export permits obtained in Step 3, often required to travel with the shipment or be referenced on the airway bill.
- Export-control screening for the material and the recipient. Biological materials, associated technical data, and even the underlying research collaboration can implicate US export-control rules (EAR/ITAR) and denied-party screening, independent of the infectious-substance rules. See Export Control (EAR/ITAR) and International Research Collaboration, What Are Dual-Use Items? EU and US Export Control Definitions, and Restricted Party Screening.
Step 5: Use a certified carrier and certified staff
Anyone who classifies, packages, marks, labels, or completes a Dangerous Goods Declaration for an infectious substance shipment needs current DOT/IATA hazmat training — this is a legal requirement, not a best practice, and it is renewed on a fixed cycle (typically every two years under the DOT rule). Not every courier handles Category A infectious substances or dry ice shipments; confirm the carrier’s capability and any embargoes on the destination route before booking, since some carriers and countries restrict or refuse Category A air shipments entirely. See Hazmat Shipping Training and Certification Requirements for Lab Staff (DOT/IATA).
A working checklist
| Step | What to confirm | When |
|---|---|---|
| 1. Classify | Category A, Category B, or exempt — against defined criteria, not assumption | Before anything else |
| 2. Package | Triple packaging built to the correct Packing Instruction; dry ice/cold-chain needs identified separately | Before booking |
| 3. Permit | Destination import permit, agricultural/biosafety permit, CITES if applicable, MTA in place | Weeks in advance |
| 4. Customs | Commercial invoice, declared value, HS code, Dangerous Goods Declaration, export-control screening | Days in advance |
| 5. Carrier | Certified DOT/IATA staff prepared the shipment; carrier accepts the material class on that route | At booking |
Frequently asked questions
Do I need a permit to ship a human blood sample internationally?
Usually yes, in some form, even when the sample itself is low-risk. The specific permit depends on the destination country’s public-health import rules and, in the US, whether the sample also falls under CDC’s Import Permit Program (for the importer, not necessarily the exporter) or an equivalent authority elsewhere. A sample that is exempt from the infectious-substance transport rules can still require an import authorization on the receiving end — classification exemption and permit exemption are not the same question.
Who is responsible for getting the import permit — the sender or the receiver?
Import permits are generally obtained by the party in the destination country (the importer/receiving lab), since the authority issuing the permit is the destination country’s own regulator. The sending lab is still responsible for correct classification, packaging, and export-side paperwork, and both sides typically need to coordinate before the material ships, since the permit is often a prerequisite the exporter needs a copy of.
What happens if a biological sample shipment is held at customs?
Outcomes vary by country and material, but a hold typically means missing or mismatched paperwork, a missing permit, or a classification the customs officer wants verified. Perishable and cold-chain shipments are especially time-sensitive in a hold, since temperature excursions can compromise the sample before the paperwork issue is resolved — which is why permits and documentation are worth finalizing before the shipment departs, not while it’s in transit.
Can I ship biological samples by international courier without special dangerous-goods training?
Not if the material is classified as an infectious substance (Category A or B) or ships with dry ice — those both trigger a legal requirement for DOT/IATA-certified personnel to prepare the shipment. Material that is genuinely exempt from the infectious-substance rules and ships without dry ice may not require hazmat certification, but confirm the exemption applies before assuming it does.
This overview is a starting point for planning, not a substitute for confirming current requirements directly with the destination country’s public-health and customs authorities, your institution’s export-control and biosafety offices, and your carrier before a shipment moves — permit rules, packing instructions, and carrier acceptance policies are all revised periodically.
