Bubble Wrap Specifications: Classes, Creep and the Shock Cutoff

Bubble is the most familiar protective material there is, and the one least often specified. Buyers order it by bubble height, a roll width and a price per foot.

A specification sits behind it all the same. The current federal document for this material dates from 2023, and it sets limits no supplier guide quotes.

Two of those limits change how the material should be bought. The pink antistatic grade carries a delivery age limit, and the cushioning requirement only applies above half an inch of thickness.

This reference covers the real purchase variables, what the spec demands, how it controls the pink class, and where its cushioning clause stops.

What You Are Buying When You Buy Bubble

Two variables carry almost every purchase. Bubble height sets how much stand-off the material gives, and roll width decides how it handles on the bench.

The spec treats height as a band rather than one figure. It sets nominal thickness across three cell height ranges: one eighth to a quarter inch, a quarter to three eighths, and anything over three eighths.

Roll width has a default too. Standard roll width in the document is 48 inches, wider than most bench rolls, which points at a converting line rather than a packing bench.

Neither variable says anything about how it performs. That part lives in the limits table, and almost nothing in the trade quotes it.

A Federal Specification Exists

The governing document is a federal item spec for cushioning material, dated 26 April 2023, which replaced a revision in force since June 1994.

Its own title is more precise than the trade name. It covers cushioning material described as closed cell and flexible plastic film, which is the technical description of what a bubble sheet is.

Two classes divide the material. Class 1 is regular film, tinted any color except pink, and Class 2 is static dissipative and pink tinted.

Both classes have to be transparent, and the document enforces that by test rather than by description. Lettering must stay legible when viewed through a single layer.

The stated purpose is broader than cushioning alone. The film is there to guard items from shock, vibration, point loads, dirt and scuffing in handling and transit.

The Requirements Nobody Quotes

The limits table is where a commodity buy turns into a spec, and every line carries its own test conditions.

Requirement	Limit	Measured at
Creep	Not more than 10%	1.0 psi for 96 hours
Reduced pressure	Not more than 4% cell failure	Altitude simulation
Heat sealability	0.79 mm (1/32 in) seam opening	Standard atmosphere
Low temperature flex	No cracks, tears or separation	−20 °F for 3 hours
Blocking	No blocking, rupture or separation	160 °F, 120 min, 1.0 psi
Abrasiveness	No scratches	10× magnification
Contact corrosivity	No corrosion, etching or pitting	Copper test surface

Creep is the one worth absorbing first. Bubble under a sustained one-pound-per-square-inch load may lose no more than a tenth of its thickness across 96 hours.

That reframes a familiar failure. Bubble that looked fine on packing day and flat on arrival need not have met any impact at all, because steady load alone has a published allowance.

Altitude gets its own clause. Reduced pressure may cause no more than 4 percent cell failure, which matters because a burst cell has stopped being cushioning.

Air freight is where that bites, and a low pressure block in a transit sequence such as ISTA 3A is the test that exercises it. A sheet that passes at sea level never faced the question.

Conditioning runs underneath all of it. Samples sit at 50 percent relative humidity and 73 °F for at least 24 hours before anyone measures anything.

The Pink Film Has an Expiry Date

Class 2 is the pink film everyone recognizes, and the specification controls it harder than the regular grade.

Its surface resistance has to land in a window, on both sides. The requirement is at least ten to the fourth ohms and below ten to the eleventh.

The window has to survive ageing as well. The same range applies after six days in a 120 °F oven, which is how the document tests whether the treatment lasts.

Then comes the clause that should change a purchase order. Class 2 film must be no more than two months old on delivery.

That age limit is the strongest published confirmation of something the ESD packaging reference already covers from the other side. A pink antistatic treatment degrades, and here a specification refuses to accept stock that has been sitting.

The document is also candid about its own limits. Class 2 is for parts open to static damage, and it points elsewhere for full protection rather than claiming to give it.

Where the Cushioning Requirement Stops

One line in the table has a condition attached, and it is the most consequential thing in the document.

Transmitted shock must fall at or below a published set of curves. That requirement applies to thickness greater than half an inch.

So most bubble on the market carries no transmitted shock limit under this specification. The thinner bands can meet every other limit and never face a question about how much shock reaches the product.

The method named above that line is the usual one for dynamic shock cushioning, the same test that yields cushion curves for any material. Calling on it only above half an inch is a choice of scope, not an oversight.

Which leaves thin bubble needing its case made elsewhere. A product fragility ceiling still applies, and nothing in a bubble height tells you whether the material clears it.

The practical reading is short. Name the class, the cell height band and the limits you actually need, and stop reading the bubble size as a performance figure.

Common Questions