A travel size changed the answer

How it happens

A mouthwash is launched at 500 mL and a 100 mL travel size is added, or the reverse. The ethanol threshold is 3 g in a single package, so the two sizes can sit on different sides of it.

Which direction surprises people

Both. A maker who cleared the large size assumes the small one is easier, and a maker who cleared the small one assumes the large one is the same product. Only the arithmetic answers it.

The fluoride mass test behaves the same way

Fifty milligrams of elemental fluoride per package. A small tube can be under it, though in practice the concentration test is the one that decides for an ordinary dentifrice.

And the exemption has its own per-unit cap

Less than 15 grams of ethanol in a single unit. So even a compliant nonremovable pump format has a size ceiling built into the exemption, which constrains the range rather than one product.

So the range is the regulatory object, not the product

A table with one row per fill volume is the only workable record. Treating the formula as the thing that was cleared is how a new size ships without a check.

This is a recurring shape

Iron in capsules, acetonitrile in nail glue remover, ethanol and fluoride here. Mass-per-package triggers all behave this way, and recognizing the shape transfers across categories.

Recompute on every size, and date it

Ethanol grams, fluoride milligrams, fluoride percentage, and the answer, per fill volume. Adding a row is a minute and it is the whole control.

The range is the object, not the formula

Every mass-per-package rule works this way, and the instinct to think of a cleared formula rather than a cleared package is what defeats it. A table with one row per fill volume fixes the instinct.

References