NBN EN ISO 7233:2008

ISO 7233:2006 specifies three methods for determining the resistance to vacuum of hoses and hose assemblies manufactured from plastic or rubber. Applicable dimensions of hoses for each method are as follows:
method A -- for hoses of nominal bore up to and including 80 mm;
method B -- for hoses of nominal bore greater than 80 mm;
method C -- for hoses of all dimensions.
Methods A and B can also be used to check the adhesion of the lining to the reinforcement (delamination) in a length of hard-wall hose or hose assembly.