18. In this Part—
“claimant” (“hawlydd”) has the meaning given in regulation 20(1);
“decision notice” (“hysbysiad penderfynu”) means a notice issued by a relevant authority under regulation 22(2)(b) or (3);
“enforcement officer” (“swyddog gorfodi”) means a person designated for the purpose of section 22 or 28 of the Act (enforcement powers) by the Olympic Delivery Authority;
“notice of claim” (“hysbysiad am hawliad”) has the meaning given in regulation 20(1); and
“relevant authority” (“awdurdod perthnasol”), in relation to the exercise or purported exercise of a power under section 22 or 28 of the Act, means—
if the exercise or purported exercise of the power was by an enforcement officer, the Olympic Delivery Authority, or
if the exercise or purported exercise of the power was by a constable, the police authority for the police force of which the constable is a member.