9. The business operator must ensure that a stunning pen used to restrain adult bovine animals for the purpose of stunning is constructed so as to—
(a)permit one animal at a time to be confined in it without discomfort;
(b)prevent any substantial movement forwards, backwards or sideways of an animal confined in it;
(c)restrict the movement of the head of an animal confined in it so as to permit accurate stunning and allow the head of an animal to be released immediately after the animal has been stunned; and
(d)allow unimpeded access to the forehead of an animal confined in it.