Oxygen transmission: rate of the closure

The standard

A declared oxygen permeability names a closure's transmission rate as mass of oxygen per year. Without it, the choice of closure is a guess about maturation.

Criteria

• The rate applies per time, not as a one-off amount
• It is a property of the closure, not of the contents
• It scatters across batches rather than being a fixed point value
• It is set in relation to the expected maturation period

Distinction

Oxygen transmission ≠ oxygen ingress: transmission is the rate through the closure, ingress the amount from all sources. Oxygen transmission ≠ closure and maturation: transmission is the measurable rate, its consequence for the wine another question. A declared oxygen permeability makes closures comparable.