Grounding of Power-Operated Tools
Power-operated tools shall be grounded under the following conditions:
-Utilization equipment used in hazardous (classified) locations (See Article 59)
-Hand-held motor-operated tools, stationary and fixed motor-operated tools, and light industrial motor-operated tools
-Motor-operated tools and utilization equipment of the following types: Drills, hedge clippers, lawn mowers, snow blowers, wet scrubbers, sanders, and saws
-Tools likely to be used in wet and conductive locations.
Notes: the followings shall not be required to be grounded:
i. Listed portable tools or utilization equipment likely to be used in wet and conductive locations if supplied through an isolating transformer with an ungrounded secondary of not over 50 volts.
ii. Listed or labeled portable tools and utilization equipment protected by an approved system of double insulation. Where such a system is employed, the equipment shall be distinctively marked.
» Double-insulated type power-operated tools are not required to be grounded.