167. In this Part:

“ADR” means—

(a) the European Agreement concerning the international carriage of dangerous goods by road,

(b) the protocol of signature to that agreement, done at Geneva on 30 September 1957,

(c) the amending protocol to that agreement adopted at Geneva on 28 October 1993 and

(d) Annexes A and B to the ADR referred to in Annexes A and B to Council Directive No. 94/55/EC of 21 November 1994 as amended;

“explosion protection document” shall be construed in accordance with Regulation 169;

“hazard” means the physico-chemical or chemical property of a substance which has the potential to give rise to fire, explosion, or other events which can result in harmful physical effects of a kind similar to those which can be caused by fire or explosion affecting the safety of a person, and cognate words shall be construed accordingly;

“risk” means the likelihood of a person's safety being affected by harmful physical effects being caused to him or her from fire, explosion or other events arising from the hazardous properties of a substance in connection with work;

“substance” includes any natural or artificial substance whether in solid or liquid form or in the form of a gas or vapour;

“workplace” means any premises or part of premises used for or in connection with work and includes—

(a) any place within the premises to which a person has access while at work, and

(b) any room, lobby, corridor, staircase, road or other place—

(i) used as a means of access to or egress from that place of work, or

(ii) where facilities are provided for use in connection with that place of work,

other than a public road.