(1)  In these regulations, a reference to –

(a) a Class of dangerous goods is a reference to the Class to which the goods are assigned under subregulation (2) ; and

(b) a Class by number, or number and letter, is a reference to the number, or number and letter, of the Class to which the goods are assigned.

(2)  Dangerous goods are assigned to a Class if the goods –

(a) are assigned to the Class in column 3 in Appendix 2 to the ADG Code; or

(b) are assigned to the Class in a Special Provision of the ADG Code applying to the goods; or

(c) satisfy the criteria in column 9 in Appendix 2 to the ADG Code for assignment to the Class; or

(d) are determined under regulation 15(c) to be dangerous goods of the Class; or

(e) satisfy the UN dangerous goods tests and criteria for assignment to the Class.