Machinery Safety 101

Understanding Safety Functions: the Safety-related stop function

A stop sign - A red octagon with a white border, and white block text reading STOP.
This entry is part of 3 in the series Under­stand­ing Safety Functions

The most used safety func­tion on machinery is the safety-related stop func­tion. The require­ments dis­cussed in this post are not gen­er­ally applic­able to pro­­cess-related stop func­tions unless the pro­cess and… 

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Manual reset using an HMI

A Siemens HMI displaying control functions and data.
This entry is part 2 of 3 in the series Under­stand­ing Safety Functions

Ques­tion: Can a safety-related stop func­tion, for example, be reset via a graph­ic­al object rep­res­ent­ing a reset but­ton on an HMI? The short answer: No, with an excep­tion. Read on if you’d like… 

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Understanding safety functions: Manual Reset

A reset button graphic
This entry is part 1 of 3 in the series Under­stand­ing Safety Functions

Fol­low­ing the risk assess­ment, risk reduc­tion is the next step. Whenev­er the con­trol sys­tem is called upon to reduce the risk, a safety func­tion is needed. Safety func­tions are defined in… 

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What is risk assessment?

This entry is part 11 of 10 in the series Risk Assess­ment

Risk assess­ment began as a dis­cip­line in the late 1960s, with some of the earli­est form­al papers pub­lished in the early 1970s. The early research­ers were part of the US military… 

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Canada’s National Day of Mourning

April 28th poster: Fight for the living, Mourn for the dead.

Fight for the Liv­ing, Mourn for the Dead On April 28th, we mourn for our work­place dead. Canada’s earli­est work­place safety legis­la­tion came into being when Ontari­o’s Fact­ory Act was passed in… 

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