ISO 7233:2016 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.