Packing Instruction 620: Packaging Category A Infectious Substances

IATA Packing Instruction 620 is the packaging specification that governs air shipments of Category A infectious substances — UN 2814 (Infectious Substance, Affecting Humans) and UN 2900 (Infectious Substance, Affecting Animals Only). It is a stricter, differently-numbered sibling to PI 650, which covers Category B (UN 3373) diagnostic and research specimens. If you have not already confirmed which tier your shipment falls into, start with Shipping Biological Substances by Air: Category A vs. Category B Classification Explained — getting that classification wrong upstream means every packaging decision below is built on the wrong requirement. This guide covers PI 620 itself: the triple-packaging construction it requires, the certification the outer packaging has to carry, and the documentation and training obligations that come with a Category A shipment specifically. A broader walkthrough of international biological shipping — permits, customs, cold chain — is covered separately in Shipping Biological Samples Internationally, which touches PI 620 briefly; this page goes deeper on the packaging spec itself.

Who PI 620 applies to

PI 620 applies specifically to Class 6.2 infectious substances assigned to Category A: material capable of causing permanent disability, or life-threatening or fatal disease, in otherwise-healthy humans or animals on exposure. That is a narrow band — most diagnostic specimens, cultures being sent for routine testing, and environmental or research samples are Category B (UN 3373) and packed to PI 650 instead, a lighter-weight version of the same triple-packaging concept without the UN performance certification requirement on the outer box. Getting the tier wrong in the direction of under-classifying is the compliance failure that actually gets shipments rejected or, worse, exposes a courier or lab-receiving-dock worker to an unmarked hazard — when in doubt, classify conservatively and consult your institutional biosafety or shipping-compliance office.

The triple-packaging system PI 620 requires

Both Category A and Category B packaging are built on the same three-layer concept, but PI 620 sets a materially higher bar at every layer:

• Primary receptacle. The leak-proof, watertight container that directly holds the infectious substance — a screw-cap vial or tube, sealed so it will not leak under normal transport conditions.
• Secondary packaging. A second leak-proof, watertight layer that fully encloses the primary receptacle. Absorbent material sufficient to absorb the entire contents of the primary receptacle(s) must be placed between the primary and secondary layers, so that a failure of the primary receptacle is fully contained before it can reach the outer packaging. If multiple fragile primary receptacles are packed together, they must be individually wrapped to prevent contact and breakage.
• Rigid outer packaging. A rigid outer box or drum that holds the secondary packaging, carries the required markings and labels, and — unlike Category B’s PI 650 — must itself be a UN-certified performance-tested packaging (see below). At least one surface of the outer packaging must have a minimum dimension of 100 mm (4 inches).

Both the primary and secondary packaging must be able to withstand, without leaking, an internal pressure differential of at least 95 kPa and the temperature range likely in transit. If the shipment also travels on dry ice or another refrigerant to maintain a cold chain, that adds a separate Class 9 (or non-hazardous refrigerant) requirement layered on top of the infectious-substance packaging, not a substitute for it — see Dry Ice Shipping Regulations: UN1845, Class 9, and Packing Instruction 954 and Cold-Chain Shipping Requirements for Biological Reagents for how the two hazard classes are handled together in the same box.

Outer packaging certification: drop test, puncture test, and the UN mark

This certification requirement is the single biggest practical difference between PI 620 and PI 650. A Category A outer packaging cannot be an ordinary rigid box — the specific packaging design (box plus its inner components, assembled as it will actually ship) must be tested and certified by the manufacturer to the UN performance-packaging standard before it can be used for a Category A shipment. The design-type testing a certified PI 620 packaging must pass includes:

• Drop test — the assembled package is dropped from a specified height onto a rigid, non-yielding surface in multiple orientations and must show no leakage of the primary receptacle’s contents.
• Puncture test — the packaging must resist a specified penetrating force without loss of containment.
• Stacking test — the packaging must withstand the compressive load of similar packages stacked on top of it for the duration of a typical shipment.
• Additional environmental checks commonly applied at certification — water-spray resistance and performance across the temperature range the packaging is rated for.

A packaging design that passes gets a UN specification mark on the outer packaging itself (a code identifying it as UN-certified for Class 6.2, Packing Group applicable, along with the manufacturer/testing details). Buying pre-certified PI 620 shipping kits from a dangerous-goods packaging supplier — rather than assembling your own outer box and hoping it qualifies — is standard practice precisely because the certification attaches to the specific tested design, not to “a sufficiently sturdy box you picked.” A shipper does not certify the packaging itself; that happens once, upstream, by the packaging manufacturer and an independent testing/approval process, and the shipper’s job is to use packaging that already carries a valid UN mark and to pack it correctly within its certified configuration (e.g., not exceeding the tested net quantity or the number of primary receptacles the design was certified for).

Marking, labeling, and the shipper’s declaration

A Category A package must carry the UN specification mark (from certification, above), the proper shipping name and UN number (e.g., “Infectious substance, affecting humans, UN 2814”), the Class 6.2 infectious-substance label, the responsible person’s name and 24-hour telephone number, and any orientation arrows the packaging requires. Category A shipments also require a completed Shipper’s Declaration for Dangerous Goods — a signed document certifying the contents are correctly classified, packaged, marked, and labeled, and are in proper condition for transport. This is a meaningful documentation difference from Category B: UN 3373 shipments under PI 650 do not require an infectious-substance label or a Shipper’s Declaration, only the UN 3373 marking and a basic set of shipping-paper information. If your shipment also crosses a border, note that the Shipper’s Declaration covers dangerous-goods classification and packaging — it does not substitute for an import/export permit, which is a separate requirement covered in Shipping Biological Samples Internationally.

Who is allowed to prepare and sign off on a Category A shipment

Because a Category A shipment carries materially higher consequences if packaged or documented incorrectly, both IATA and U.S. DOT restrict who may classify, package, mark, and sign the Shipper’s Declaration for one. Under IATA’s Dangerous Goods Regulations, personnel who prepare Category A shipments must complete dangerous-goods training specific to infectious substances, with recurrent training required on a fixed cycle (commonly cited as every 24 months under IATA’s framework) rather than a one-time credential. In the United States, hazmat employee training obligations for anyone who classifies, packages, marks, labels, or documents these shipments are set out in 49 CFR 172.704, which requires function-specific and safety training with recurrent training at a set interval; self-certification is permitted only when the training itself is properly documented and the records retained. For the full scope of who needs to be trained and how the initial/recurrent cycle works at your institution, see Hazmat Shipping Training and Certification Requirements for Lab Staff (DOT/IATA). For the broader air dangerous-goods framework PI 620 sits inside, see IATA Dangerous Goods Regulations: A Lab Shipper’s Guide.

PI 620 vs. PI 650 at a glance

• Applies to: PI 620 — Category A (UN 2814/UN 2900). PI 650 — Category B (UN 3373).
• Outer packaging: PI 620 requires UN-certified, performance-tested outer packaging (drop/puncture/stacking tested). PI 650 requires rigid outer packaging but no UN performance certification.
• Labeling: PI 620 requires the Class 6.2 infectious-substance label. PI 650 requires only the UN 3373 diamond-shaped marking, not a hazard label.
• Documentation: PI 620 requires a signed Shipper’s Declaration for Dangerous Goods. PI 650 does not.
• Shipper training: PI 620 shipments must be prepared by personnel with current dangerous-goods/infectious-substance training. PI 650 has lighter training expectations, though institutions commonly train staff to the same standard for both to avoid misclassification risk.

Frequently asked questions

Is Packing Instruction 620 an IATA rule, a DOT rule, or both?

PI 620 is IATA’s packing instruction for air transport, part of the IATA Dangerous Goods Regulations, which are themselves built on the UN Model Regulations. U.S. DOT’s ground-transport rules (49 CFR Parts 171–180) require materially equivalent triple-packaging and certification for Category A infectious substances, so a package built to PI 620 will generally satisfy both frameworks, but always confirm against the current edition of whichever regulation governs your specific shipment (air vs. ground, carrier-specific variations) rather than assuming automatic equivalence.

Can I build my own PI 620-compliant outer packaging in-house?

Only if that specific design has gone through UN performance-package certification testing and carries the resulting UN mark. In practice, nearly every lab buys pre-certified PI 620 kits from a dangerous-goods packaging supplier rather than certifying its own design, since the testing and approval process is done once by the manufacturer, not per shipment.

Does PI 620 packaging expire or need to be re-tested?

The certification attaches to the packaging design and manufacturing process, not an individual box’s service life in the way a use-by date would, but a shipper must use the packaging within the manufacturer’s stated configuration (net quantity limits, number/size of primary receptacles) and should not reuse packaging that shows damage, since a damaged box no longer represents the certified, tested design.

What happens if a Category A shipment is packed to the PI 650 (Category B) standard instead?

It is a misclassification with real consequences — PI 650 packaging is not UN performance-certified and does not carry the infectious-substance label or Shipper’s Declaration a Category A shipment legally requires, so the shipment can be refused at carrier acceptance, and if it were to leak in transit, the containment margin is materially lower than what PI 620 is engineered to provide. This is the exact reason classification comes first: see Category A vs. Category B Classification Explained.