Hi,
a good way to guarantee absolute darkness with adequate airflow is to shop
for darkroom (photography) supplies - products specifically designed to let
absolutely NO light in, without cutting off all the oxygen.
 
Dooks,
Niki with Chili, Chuckles, Pixie, Carbon and Buttons
P.S.  In case somebody already mentioned that - sorry, didn't keep up
recently
[Posted in FML issue 2512]