Energy sources on a typical dough mixer
Every machine is different: check your model's nameplate, wiring and the manufacturer's manual. This is where most dough mixers get their energy and how it is usually isolated.
| Energy | Typical magnitude | Isolating device | How to control it |
|---|---|---|---|
| Electrical | 208–480 V, 3-phase (hard-wired) or 120/240 V (cord and plug) | Main disconnect switch on the wall or machine panel (or plug, if cord-connected) | Switch the disconnect to OFF and apply a lock and tag. If cord-connected, unplug and fit a plug lockout cover. |
| Stored mechanical (motion, springs, tension) | Agitator and bowl inertia after stop | None — wait for complete stop | Wait until the agitator and bowl have fully stopped before opening the guard. |
| Gravity (raised or suspended parts) | Raised bowl or mixing head (bowl-lift and tilt-head models) | Bowl lowered or mechanically blocked | Lower the bowl to its rest position, or block the head with the manufacturer's support before reaching under it. |
Shutting it down
- Stop the mix cycle with the normal STOP control and wait for the agitator to stop.
- Set the speed selector and timer to OFF.
- Lower the bowl (bowl-lift models) or return the head to its locked position.
Releasing stored energy
- Confirm the agitator and bowl are not moving.
- Make sure the bowl or head cannot drop: lowered fully, or blocked with the manufacturer's support.
Verifying isolation
- Press START with the bowl guard closed: the machine must not start. Return the control to OFF.
- Try to jog or rotate the bowl with the controls: no movement.
Things people miss
- The bowl guard interlock is not an energy isolating device and must not replace lockout.
- Cord-and-plug models: unplugging is enough only if the plug stays under the exclusive control of the person working on the mixer (OSHA 1910.147(a)(2)(iii)(A)).
Turn this into your written procedure
Add your company, the machine ID, the voltage and where each disconnect and valve is. You get a machine-specific procedure that follows the structure of 29 CFR 1910.147(c)(4), with an approval block and printable DANGER tags.
Start with the dough mixer templateQuestions
Does a dough mixer need its own lockout procedure?
OSHA 29 CFR 1910.147(c)(4) requires documented procedures for the control of hazardous energy. A procedure is not required only when all eight conditions of the exception in (c)(4)(i) are met, for example a single energy source that can be readily identified and isolated. Most machines with more than one energy source need a written, machine-specific procedure.
Is unplugging enough?
For cord-and-plug equipment, the lockout standard does not apply when the equipment is unplugged and the plug is under the exclusive control of the employee doing the work (1910.147(a)(2)(iii)(A)). If the plug can be out of sight or reach, use a plug lockout cover with a personal lock.
Is the interlocked guard enough?
No. Guard interlocks and emergency stops are not energy isolating devices and do not replace lockout during servicing, cleaning or clearing jams.
General information, not legal advice. Verify every energy source on the actual machine and have the procedure approved by a qualified person.