Like this one from OSHA:
(b) Machine controls and equipment. (1) A mechanical or electrical
power control shall be provided on each machine to make it possible for
the operator to cut off the power from each machine without leaving his
position at the point of operation.
(2) On machines driven by belts and shafting, a locking-type belt
shifter or an equivalent positive device shall be used.
(3) On applications where injury to the operator might result if
motors were to restart after power failures, provision shall be made to
prevent machines from automatically restarting upon restoration of
power.
(4) Power controls and operating controls should be located within
easy reach of the operator while he is at his regular work location,
making it unnecessary for him to reach over the cutter to make
adjustments. This does not apply to constant pressure controls used only
for setup purposes.
(5) On each machine operated by electric motors, positive means
shall be provided for rendering such controls or devices inoperative
while repairs or adjustments are being made to the machines they
control.
(6) Each operating treadle shall be protected against unexpected or
accidental tripping.
(7) Feeder attachments shall have the feed rolls or other moving
parts so covered or guarded as to protect the operator from hazardous
points.
