Safety starts at the switch: Do your portable power tools comply?
Between October 2022 and September 2023, OSHA issued 91 citations and more than $400,000 in penalties for general industry violations of the standard for guarding portable power tools. General industry employers are responsible for ensuring the safe condition of the portable powered tools workers use, including tools the employees furnish.
Types of switches and controls
The general industry regulations at 29 CFR 1910.243 mandate the types of power switches and controls specific portable power tools must have. Before drilling into requirements, it’s important to distinguish between the kinds of switches and controls workers encounter on power tools.
Constant pressure switch or control
To operate a power tool with a constant pressure switch or control, the worker would apply pressure to the power switch to turn it on and continue applying pressure to the switch to keep the power on. Releasing the switch automatically shuts off the tool’s power.
Constant pressure throttle control
A constant pressure throttle control adds another level of safety to a constant pressure switch or control. To turn on a power tool and keep it running, first hold the throttle, usually a lever near the power switch, and then apply pressure to the switch. When a throttle isn’t engaged, the switch won’t work.
Like a constant pressure switch or control, continuously hold the throttle to keep the power on. Releasing pressure from the throttle shuts off the tool’s power automatically.
Lock-on control
Only certain portable power tools with a constant pressure switch or control allow lock-on control. To use a tool with this type of control, hold the power switch and then activate the lock-on control (such as pressing a button) to keep the switch in the on position.
When the lock-on control is activated, the power stays on after releasing the switch. Pressing the switch again disengages the lock-on control, and releasing the switch turns off the power.
Positive “on-off” control
For a power tool with a positive on-off control, the worker would press the power switch once to turn it on and once again to turn it off. This type of control doesn’t require constant pressure on the switch to maintain power.
Switch and control requirements
OSHA requires certain types of switches and controls for specific power tools. Additionally, a portable power tool’s operating control must be in a place that minimizes the possibility of its accidental operation if such an event poses a hazard to employees.
Constant pressure switch or control
A constant pressure switch or control must be on these handheld power tools without positive accessory holding means:
- Circular saws with a blade diameter greater than 2 inches;
- Electric, hydraulic, or pneumatic chain saws; and
- Percussion tools.
Constant pressure switch or control with optional lock-on control
A constant pressure switch or control must also be on the following handheld power equipment:
- Drills;
- Tappers;
- Fastener drivers;
- Horizontal, vertical, and angle grinders with wheel diameters greater than 2 inches;
- Disc sanders with disc diameters greater than 2 inches;
- Belt sanders;
- Reciprocating saws;
- Saber, scroll, and jig saws with blade shanks greater than a nominal 1/4 inch; and
- Other similarly operating powered tools.
These tools can have a lock-on control only if the turnoff can be achieved by a single motion of the same finger or fingers that turn it on.
Constant pressure throttle control
All handheld gasoline-powered chainsaws must have a constant pressure throttle control.
Positive on-off control
All other handheld power tools can have either a positive on-off control or constant pressure switch or control that meets the applicable requirements at 1910.243(a)(2)(i) and (ii). These include, but aren’t limited to:
- Platen sanders;
- Grinders with wheel diameters of 2 inches or less;
- Disc sanders with disc diameters of 2 inches or less;
- Routers;
- Planers;
- Laminate trimmers;
- Nibblers;
- Shears; and
- Saber, scroll, and jig saws with blade shanks a nominal 1/4 inch wide or less.
Take control of power tool safety
Employers are responsible for ensuring that all portable power tools their workers use are in safe condition and meet OSHA’s safety standards, including the switch and control requirements.
Consider these tips to help you keep your portable power tools compliant and the workers who use them safe:
- Inventory portable power tools and determine whether they meet the standards.
- Remove from service and replace tools that don’t comply.
- Inform your employees of the switch and control requirements so they know which tools to use.
- Evaluate employee-furnished tools for compliance before allowing their use on the job.
- Make sure new tools align with OSHA’s regulations before purchasing them.
Key to remember
The place where safety starts is at the tool’s power switch.


































































