摘要 |
A hose or tube for transporting a gas specimen has an inner envelope, forming a diffusion barrier and containing a plurality of perforation holes, and an outer envelope, forming a diffusion layer and resting on the inner envelope. The object is to develop a hose or tube so as to ensure transport of a gas specimen over as great a distance as possible without substantial weakening of the concentration, and at the same time without impairing the ability of the gas to be detected to diffuse into the hose or tube. For this purpose, the outer envelope contains diffusion-inhibiting sealing zones on its inner surface, which zones overlap the perforation holes in the inner envelope. |