Arc fault protective devices

1.1
This Standard applies to arc fault protective devices designed to be installed in accordance with the Rules of the Canadian Electrical Code, Part I. 

1.2
These devices include arc fault circuit interrupters (AFCI) and devices that incorporate arc fault circuit protection for use on single phase, 120 V, or single phase, two-pole, three-wire 120/240 V alternating current, 60 Hz circuits having a maximum current rating of up to 20 A for permanently connected and up to 30 A for cord-connected. 

1.3
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 (non-mandatory) to define their application.