# Vacuum Tank Query (Aluminium, Carbon Fibre, etc, Composition)

Baluncore
2019 Award
So carbon fibre is a gas-permeable material (ie not "vacuum-tight")? But aluminium/stainless steel are not gas-permeable?
The choice of material will be decided by contamination and leakage rate.
What is the vacuum connected to?
You have failed to identify the application of the vacuum tank, so the leakage rate and potential for contamination cannot be assessed.
Why is the use of the vacuum confidential?

You have failed to identify the application of the vacuum tank, so the leakage rate and potential for contamination cannot be assessed.
Why is the use of the vacuum confidential?
By definition, I can't provide a meaningful reply to that question

Baluncore
2019 Award
By definition, I can't provide a meaningful reply to that question
By definition of what ?

berkeman
Mentor