National Electrical Code Articles and Information

1. [250.124(A)]. Those provided in drawout equipment or attachment plugs (and mating plugs and receptacles) must be first-make, last-break unless interlocks preclude energization without grounding (bonding) continuity.
    

2. [250.124(B)]. Yes, but only if opening the switch disconnects all sources of energy.
    

3. [250.126]. A green screw (not readily removable), green hex nut, or green pressure wire connector.
    

4. [250.126]. The entrance hole must be marked with the word green or ground, the letters G or GR, or by a distinctive green color.
    

5. [Table 250.122]. Zero. The minimum sized Equipment Grounding Conductor is 14 AWG. It can accommodate a 15A circuit. If you had a mix of 15A and 20A circuits, it would make sense to use just the larger EGC (#12) or if you have high harmonics use a #10 EGC.