Presents three methods for determining resistance of outer cover of hoses to ultra-violet light: Method 1: for bore sizes up to 25 mm, carried out on hose itself; Method 2: for bore sizes above 25 mm, carried out on hose itself; Method 3: for bore sizes above 25 mm, carried out on a piece from hose cover. Method 1 or 2 should normally be used. Method 3 should be used only if method 2 cannot be employed.