Section R. 408.13823 - ControlsRule 3823.
(1) A hand-held powered circular saw having a blade diameter more than 2 inches; an electric, hydraulic, or pneumatic chain saw; and a percussion tool without positive accessory holding means shall be equipped with a constant pressure switch or control that will shut off the power when the pressure is released. A gasoline-powered, hand-operated tool shall be equipped with a constant pressure throttle. A throttle position lock may be provided for starting only.(2) All of the following hand-held tools shall be equipped with a constant pressure switch or control and may have a lock-on control if turn off can be accomplished by a single motion of the same finger or fingers that turn it on: (d) Grinder with a wheel more than 2 inches in diameter.(e) Disc sander with disc more than 2 inches in diameter.(j) Jig saw with a blade shank more than a nominal 1/4 inch.(k) Similarly operating power tools.(3) Other hand-held powered tools, such as, but not limited to the following, may be equipped with either a positive on-off control or other control prescribed in subrules (1) and (2) of this rule: (b) Grinder with a wheel 2 inches or less in diameter.(c) Disc sander with discs 2 inches or less in diameter.(k) Jig saw with blade shank of a nominal 1/4 inch or less.(4) The operating control on a hand-held power tool shall be located so as to prevent accidental operation, if such operation would constitute a hazard to an employee.(5) A hand-held power tool shall be disconnected from its power source when it is serviced or the point of operation device is changed by a device or tool, except for a hand-held drill less than 3/8 inch, platen sander, 2 inch belt sander, or scroll saw.(6) Subrule (1) to (5) of this rule do not apply to the following: (g) Household and kitchen appliances.(h) Personal care appliances.(i) Medical or dental equipment.(j) Fixed machinery or equipment.Mich. Admin. Code R. 408.13823