1.1 This Standard applies to appliance plugs used as components of heater cord sets for use on cord- connected heating appliances rated for use on nominal single-phase system voltages of 240 V and less, designed to be used in dry nonhazardous locations in household and similar applications in accordance with the Canadian Electrical Code, Part I. 1.2 In this Standard, ?shall? is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; ?should? is used to express a recommendation or that which is advised but not required; and ?may? is used to express an option or that which is permissible within the limits of the standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (nonmandatory) to define their application.