CR Packaging Retesting: When a Design Change Actually Requires Recertification

CR certification is configuration-specific by design

Child-resistant packaging is certified through the 16 CFR 1700.20 testing protocol against a specific, exact package configuration, a defined container, closure, wall thickness, and material combination tested together as a unit. The certification does not automatically extend to a "similar" package; it applies to the tested configuration and only that configuration.

Changes that typically trigger retesting

Wall thickness changes, even small ones, can alter how a closure seats and torques, changing the force required to open it. Resin changes, including a shift to a different regrind ratio or a different resin supplier's formulation of the same nominal material, can change stiffness and friction characteristics at the closure interface. Color additive changes are a commonly overlooked trigger: certain pigments and masterbatches can subtly change a resin's mechanical properties at the closure, enough to shift CR performance even when the visual change is the only thing anyone intended.

Changes that generally don't require retesting

Label changes, printing changes, and other purely cosmetic surface treatments that don't touch the container or closure geometry, wall thickness, or resin formulation typically don't affect CR performance and don't require retesting on their own. The distinguishing question is always whether the change could plausibly affect how the CR mechanism physically functions, not whether the part looks different.

What this means for ongoing production

Any packaging change request, from a brand, a cost-reduction initiative, or a supplier switching a raw material source, should be checked against this list before being approved for a CR-certified product, not after it's already in production. A change that seems purely cosmetic can sometimes be the one that actually needs a retest, and a change that looks structural can sometimes fall within the tested tolerance. When in doubt, ask the certifying lab rather than assuming.

How we manage this

We flag any proposed change against CR retest triggers before implementing it on a certified product, and maintain configuration documentation tied to each certification so it's clear exactly what was tested. For the certification fundamentals, see What Child-Resistant Packaging Actually Requires.

See our cannabis packaging capabilities, or request a quote.