Military Packaging Methods: Five Codes, and What Sits Under Them

A contract line reads Method 50, and the job looks settled until someone opens the standard, where that number turns out to be a pointer rather than a recipe.

Military packaging runs on a coded string of fixed-width fields. One field holds the method of preservation, and a dozen others hold cleaning, wrap, cushioning, containers, level and marking.

The method field then has two layers of its own. Five numbers sit at the top. Submethods beneath them decide whether the item ships in a bag, a box, a sealed can, or a bag floating inside an outer container.

That second layer is where most of the real difference lives, and it is the part that rarely survives into a summary, a quote or a supplier email.

This reference covers the code the number sits in, the methods and submethods beneath it, why cushioning gets no method, and what the appendix tables decide.

The Method Number Is One Field Among Many

The packaging requirement code is a row of fields, each one a fixed width. Read across, it describes a whole unit pack rather than a single step.

Quantity per unit pack comes first, up to 999 in the clear, with BLK for bulk and ZZZ for anything special.

The method itself takes two digits. Cleaning and drying takes one, preservative two, wrap two, cushioning or dunnage two, and thickness one.

Containers follow with two digits each, then a level code saying whether that unit container may ship alone, and a letter covering swaps.

So the method answers one question out of a dozen, and quoting it alone leaves cleaning, wrap, cushioning and marking blank.

Five Methods, and the Submethods That Decide the Pack

The five top numbers separate by what they keep out. Method 10 is physical protection, and Method 20 is a coating applied after cleaning and drying.

The last three build a barrier. Method 30 keeps out water, Method 40 keeps out water vapor, and Method 50 adds desiccant inside the sealed barrier.

Each of those three carries submethods, and that layer carries the weight. The same Method 40 can mean a bare sealed bag or a bag inside a rigid box.

Code	What the submethod calls for
31	Waterproof bag, heat sealed
32	Container, waterproof bag, heat sealed
33	Greaseproof-waterproof bag, heat sealed
41	Watervaporproof bag, heat sealed
42	Container, bag, heat sealed, then container
43	Floating watervaporproof bag, heat sealed
44	Rigid container, other than metal
45	Rigid metal container, sealed
51	Watervaporproof bag with desiccant, heat sealed
52	Container, bag with desiccant, then container

Method 50 also adds two items the packer has to put in by hand. A humidity indicator goes in beside the desiccant, and the pack carries its own label.

How much desiccant never appears in the method. It follows from formulas tied to barrier area and enclosed volume, so a desiccant calculation settles the unit count.

The floating submethods go missing most often. The packer seals the bag, then suspends it inside an outer container, anchoring or shock mounting the item as needed.

Cushioning Is Not a Method

None of the five numbers is a cushioning method. Cushioning appears inside them as a supporting clause and nowhere as a method of its own.

Method 10 asks for cushioning as required to protect the item, while the barrier methods ask for it against shock and vibration.

The deciding number is the fragility factor, which the standard defines as the highest G level an item survives, without damage, while switched off.

Two thresholds appear in the decision figure, at 50 G and 85 G, and items in the common group have to clear 85 G or more.

Below those lines the pack does real work, and a product fragility figure is what sizes it. Picking a thickness without that number is guesswork, and cushion curves match a material to it.

The Codes Are Pointers, Not Specifications

Each two-digit field points into a lookup table, and those tables are the bulk of the document. The method list sits on page 147.

Material codes follow on page 160, thickness codes on page 164, and the fragility table sits much earlier on page 29.

Exemptions live outside the digits too. Items already protected by VCI packaging are exempt from preliminary wrapping, and so is hard film of certain grades once dry.

Barrier choices sit in their own documents rather than in the method number, and the same holds for ESD packaging, where a separate document governs.

So the practical approach stays short. Read the whole code rather than the method field, and treat the two digits as a question the appendix tables answer.

Confirm the revision first. The copy read here is the 2019 edition with its fourth change, and the standard itself says to verify the current issue.

Then check what the method does not cover, because desiccant quantity, cushioning thickness, barrier material and marking all sit in other fields or other documents.

None of that makes the number useless. It makes it an index entry, and reading it that way splits a pack that clears inspection from one that comes back.

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