What goes wrong

The jar was not the package

Updated October 2026

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The six, in order The closure restraint is the one people miss Absorbent is a quantity requirement Non-reactive matters with preservatives Prototype testing means the whole assembly And the quantity limit sits above all of it If it does not fit, ship it properly Read the section, not a summary of it References

A good jar, properly capped, satisfies one of six conditions.

The six, in order

Quantity per inner receptacle, the receptacle’s material and fill, the closure held by positive means, non-reactive absorbent able to take the whole contents, a strong outer packaging, and prototype testing of the completed package. A jar answers part of the second.

The closure restraint is the one people miss

Held securely in place with wire, tape, or other positive means. That is not a torque specification, it is a physical restraint added after capping, and a well-liner-sealed cap does not substitute for it.

Absorbent is a quantity requirement

Capable of absorbing the entire contents of the receptacle. A pad that catches a splash is not that, and the arithmetic is simple enough to do before packing rather than after a leak.

Non-reactive matters with preservatives

The absorbent must not react chemically with the material. That rules out some common packing materials with some preservatives, and it is a question for whoever supplies the absorbent.

Prototype testing means the whole assembly

The completed package, as demonstrated by prototype testing. So the thing that gets tested is the box with everything in it, not the jar, and swapping any component reopens the test.

And the quantity limit sits above all of it

Thirty milliliters per inner receptacle. Our smallest jar is 55 mL, so for this route the receptacle comes from elsewhere and these jars hold the collection rather than travel with it.

If it does not fit, ship it properly

A properly classified, marked, labeled and documented hazardous materials shipment is the alternative, and it is a specialist job. Pretending an exception applies is the failure this page is about.

Read the section, not a summary of it

Six conditions in one subsection is short enough to read in full, and every condition has a number or a material in it. A paraphrase, this one included, is for deciding whether to open the section rather than for deciding whether a package qualifies.

References

49 CFR 173.4, Small quantities for highway and rail. Class 3 and other listed materials are not subject to other requirements where the inner receptacle holds no more than 30 mL of liquid, is not liquid-full at 55 C, is glass, earthenware, metal or plastic of at least 0.2 mm, has any removable closure held securely with wire, tape or other positive means, and is packed with non-reactive absorbent able to take the entire contents inside a strong outer packaging, the whole demonstrated by prototype testing. law.cornell.edu

49 CFR 173.4b, De minimis exceptions, which take listed Packing Group II and III materials out of the definition of a hazardous material at 1 mL per inner receptacle for liquids, subject to five specified 1.8 m drops and a compressive load. law.cornell.edu

Written from federal statute and regulation, not from a collection room. Wildlife law is federal, state and sometimes tribal at once, and the Lacey Act makes a state or foreign violation a federal matter. Nothing here is advice on a particular specimen, and the permit questions belong to the Fish and Wildlife Service.