# Diffusion length and time screening
# Scope: One-dimensional characteristic diffusion timescale L squared over 2D.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

distance = 1 mm
diffusivity = 0.000000001 m^2/s

duration := distance^2/(2*diffusivity) [s]

check diffusion time budget: duration <= 600 s

scenario alternative: distance = 0.8 mm