The Bottles Directive lets a bottle do double duty as a measuring container, replacing what would otherwise be twenty-seven national metrology rules.

It applies to bottle manufacturers, importers, fillers and packagers, distributors and retailers, for closed or closable bottles of glass or an equally rigid material intended to hold, transport or deliver a liquid.

A conforming bottle carries the reverse-epsilon mark, its actual capacity stays within the permitted tolerance for its nominal capacity, and it bears the manufacturer's identification mark registered with the authority.

You confirm the bottle is meant as a measuring container, produce it within the tolerances, register your identification mark, mark the nominal capacity in the prescribed form, apply the reverse-epsilon mark only where the bottle conforms, and keep production records.

Conphora maps your bottles against the Directive, flags gaps in capacity, tolerances, the identification mark and the certifying mark, and alerts you when the rules change.

The full guide is at conphora.com.