Emergency Stop buttons, or E-Stops, are an important component of machine safety.  While they are not considered a safeguarding device, since they do not prevent access to a hazard, they are often a necessary and required control on machinery.

If you are installing an E-stop, or already have one, you’ll want to make sure that it meets the CSA requirements.

1.       E-stops shall override all other machine controls and cause all moving parts to stop,

2.       E-stops shall be red, mushroom head style,

3.       E-stops shall have a yellow background,

4.       E-stops shall be unguarded and easily accessible, and

5.       E-stops shall require manual re-setting and shall not initiate a cycle start.

The E-stop in the figure on the left fails on two accounts.  It performs like a push button and does not stay de-pressed when activated. It also is not red in colour. The figure on the right shows a proper E-stop.