Getting started

From formula to bottle

Updated October 2026

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One: establish the elemental iron per unit Two: decide the fill count Three: run both tests Four: if it applies, the packaging has to be tested And it may not be reused Then the ordinary pack decisions Keep the calculation per count Two of the four steps are per size References

Four steps, and the third one cannot be answered until the second is.

One: establish the elemental iron per unit

Elemental iron, from any source, not the weight of the iron compound. Ferrous sulfate, fumarate and bisglycinate all deliver different elemental iron per milligram of salt, and the rule counts the element.

Two: decide the fill count

Because the threshold is per package. Thirty, sixty, ninety, one hundred and eighty are all different regulatory positions for the same capsule, and so is a fourteen-count trial pack.

Three: run both tests

Elemental iron per unit times the count, against 250 mg. And the concentration of elemental iron in the product, against 0.05 percent weight-to-weight for a solid. You need both to be over before the requirement applies.

Four: if it applies, the packaging has to be tested

Not a closure described as child-resistant, but a package meeting the effectiveness specifications in 1700.15 and continuing to meet them in contact with the contents and across the customary openings and closings.

And it may not be reused

1700.15(c) says special packaging under those paragraphs shall not be reused, which closes off a refill proposition for an iron-containing supplement before the marketing is written.

Then the ordinary pack decisions

Induction seal for tamper evidence and moisture, desiccant sized to the headspace, cotton or a filler if the capsules would rattle and chip, and a label that fits the Supplement Facts panel.

Keep the calculation per count

A table with one row per fill count, dated, showing elemental iron per unit, the package total and the concentration. Adding a size reopens the first two columns and nothing warns you.

Two of the four steps are per size

Which makes this a table rather than a checklist. A line with a 30, a 60 and a 180-count is three sets of arithmetic, and the one added last is the one that never gets run.

References

16 CFR 1700.14(a)(13), Dietary supplements containing iron, requiring special packaging where a supplement contains the equivalent of 250 mg or more of elemental iron from any source in a single package at 0.025 percent or more weight-to-volume for liquids or 0.05 percent or more weight-to-weight for nonliquids, excepting iron present solely as a colorant and powdered preparations at no more than 0.12 percent weight-to-weight. law.cornell.edu

16 CFR 1700.15, Poison prevention packaging standards: not less than 85 percent child-resistant effectiveness without a demonstration and 80 percent after one, the packaging must keep working in actual contact with the substance and across the openings and closings customary for its size and contents, and special packaging under those paragraphs shall not be reused. law.cornell.edu

21 CFR 101.36, the Supplement Facts panel for dietary supplements, which sets the required nutrition labeling and its format. law.cornell.edu

Written from federal regulation and from measured catalog data, not from a packaging line. Whether a product crosses the iron threshold is a calculation about your formula and your fill count, and the figures here are the test rather than the answer. Nothing on these pages certifies a package as child-resistant; 16 CFR 1700.15 tests the assembly, not the cap.