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How to Use a Gotcha Stick

John Guckin
Posted by John Guckin on Mar 31, 2022 11:30:00 AM

gaurd w Gotcha stick copy

Hello, I'm John Gucking from MPSA Safety, and today I'm going to tell you how to use a Gotcha Stick and why it's essential for machine safety. But, before diving in, let's review the goal of any Gotcha Stick. 

The primary purpose of a Gotcha Stick is simple: to test barrier guard openings near machine hazards and determine whether or not the guard openings are compliant with OSHA and ANSI machine safety standards. 

Keep reading or watch our Gotcha Stick tutorial for more information on using a Gotcha Stick.


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What is a Gotcha Stick? | Gotcha Stick History |Different Types of Gotcha Sticks |

Why is Compliance Important? | How to use a Gotcha Stick? |  MPSA Safety Trainer | Summary | Resources & Information 



What is a Gotcha Stick? 

MPSA Gotcha Stick (1)

A Guard Opening Scale, AKA a "Gotcha Stick," is a tool used to ensure machine barrier openings are compliant with up-to-date machine safety standards. 

The Gotcha Stick physically tests the measurements between guard openings and machine hazards, quickly determining whether or not the guard openings are safety standard compliant. Testing machine barrier openings with a Gotcha Stick helps ensure the barrier guarding is at a safe distance away from the hazard. 

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Or request a safety risk assessment from one of our machine safety experts and receive a FREE Gotcha Stick when we visit your facility.


Gotcha Stick History  

Hands Out

Since the early 1940s, people’s assumptions about machine safety haven’t always been correct. Many people once assumed that as long as a machine had some guarding, the staff was safe from machine hazards. That was swiftly debunked when teams working with presses and lathes without proper machine safety guarding soon faced many injuries, amputations, and even deaths. 

So, in 1948 Liberty Mutal Insurance collaborated with the Writing Committee for the ANSI B11.1 Safety Standard on Mechanical Power Presses to engineer a stair-step-shaped measurement tool to determine the minimum safe distance between a guard opening's distance to the nearest point-of-operation hazard. For the last 70 years, the Gotcha Stick has proven to be the most effective way of ensuring barrier guard openings will not allow a dangerous zone to be accessed. 


Different Types of Gotcha Sticks

gotcha stick

Today, there are two types of modern Gotcha Sticks. The OSHA Compliance Gotcha Stick and the ANSI scale Gotcha Stick. These separate tools test for conformance to the measurements set forth by OSHA regulations from 1971 and by ANSI and CSA standards. Check out our Standards & Regulations page for up-to-date safety standards.  


Why is Compliance Important? 

mpsa standMost importantly, being compliant with OSHA and ANSI regulations protects workers and save lives, but it also has many financial benefits for businesses. Without them, companies risk exposing staff to potential machine hazards. That's why it's essential to create a safe working environment and eliminate potential hazards with the Gotcha Stick. 

Visit our Standards & Regulations page for up-to-date OSHA and ANSI standards and regulations.

How Do You Use a Gotcha Stick? 

A Gotcha Stick mimics the human hand and forearm to ensure hazards are at a minimum safe distance. Remember, though, that the Gotcha Stick is a two-dimensional representation of three-dimensional human body parts. Thus, engineers must use proper techniques to ensure barrier guards are measured at a minimum safe distance from the hazard.

Watch our video tutorial here 

gotcha stick gif

You'll first attempt to touch the Hazard with the Gotcha Stick by putting the smaller, scaled side of the stick into the guarding that surrounds the hazard you wish to test.

If designed correctly, the barrier guard will stop the small end of the Gotcha Stick from touching the hazard area. However, if the Gotcha Stick touches the hazard, the machine guards are too close to the hazard, which means your machine guarding is not compliant and someone could potentially be injured. 

You can fix the unsafe machine guarding in one of two ways; move the guard further away from the hazard, make the adjustable guard opening smaller, or a combination of the two solutions.

  1. Proper Use Tips:  

  •  Measure multiple openings of all different sized holes in a barrier guard—each different size must be tested with the Gotcha Stick. 

  • The maximum guard opening OSHA allows is a five-inch opening at 36 inches away. 

  • All barrier openings should always be measured empty, not with any material in place.
  •  Adjustable guard openings must be measured just the same as fixed guard openings.
  1. MPSA Ruler 2018 FINAL_Page_1


Lastly, when using the Gotcha Stick, keep in mind that your machine guard openings size determines the minimum safe distance from a hazard. In addition, different barrier openings have different minimum safe distance requirements and OSHA and ANSI standards. For more information on how to use the Gotcha Stick, review the minimum safe distance measurements for known gap sizes printed on the backside of the tool. 



Need training on machine safeguarding concepts? 

Meet the MPSA Safety Trainer!



MPSA's portable machine safety trainer uses five access points to teach students and personnel about compliant vs. non-compliant machine safeguarding methods.

Think again if you have implemented a safe and compliant safety control system! Our safety trainer demonstrates how the improper selection or utilization of safety components can leave you with a non-compliant solution. Ask an expert about purchasing one for all your training needs.




Today's blog reviewed how to use a Gotcha Stick to help ensure your guarding is a minimum safe distance from a hazard. You can purchase a Gotcha Stick on our website or receive one FREE by requesting a machine hazard assessment from our safety professionals at MPSA.

Ask a Machine Safety Expert

Buy Gotcha Stick

Or request a safety risk assessment from one of our machine safety experts and receive a FREE Gotcha Stick.

Resources & Information 

Request a Machine Hazard Assessment & Receive a FREE Gotcha Stick! 

Shop Gotcha Stick 

MPSA Safety Trainer 

Standards & Regulations 

MPSA Turnkey Machine Guarding 


Topics: Machine Safety, Explainers, Tutorials

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