Machinery Safety 101

How to do a 13849 – 1 analysis: Complete Reference List

This entry is part 8 of 9 in the series How to do a 13849 – 1 analysis

Post updated 2019-07-24. Ed. As prom­ised in pre­vi­ous posts, here is the com­plete ref­er­ence list for the series “How to do a 13849 – 1 ana­lys­is”! If you have any addi­tion­al resources you… 

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ISO 13849 – 1 Analysis — Part 8: Fault Exclusion

This entry is part 9 of 9 in the series How to do a 13849 – 1 analysis

Post updated 2019-07-24. Ed. Fault Con­sid­er­a­tion & Fault Exclu­sion ISO 13849 – 1, Chapter 7 [1, 7] dis­cusses the need for fault con­sid­er­a­tion and fault exclu­sion. Fault con­sid­er­a­tion is the pro­cess of examin­ing the… 

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ISO 13849 – 1 Analysis — Part 6: CCF — Common Cause Failures

This entry is part 6 of 9 in the series How to do a 13849 – 1 analysis

Post updated 2019-07-24. Ed. What is a “Com­mon Cause Fail­ure”? There are two sim­il­ar-sound­ing terms that people often get con­fused: Com­mon Cause Fail­ure (CCF) and Com­mon Mode Fail­ure. While these… 

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31-Dec-2011 – Are YOU ready?

This entry is part 8 of 8 in the series Cir­cuit Archi­tec­tures Explored

31-Decem­ber-2011 marks a key mile­stone for machine build­ers mar­ket­ing their products in the European Uni­on, the EEA and many of the Can­did­ate States. Func­tion­al Safety takes a pos­it­ive step for­ward with the… 

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Interlock Architectures Pt. 6 – Comparing North American and International Systems

industrial Control Console
This entry is part 6 of 8 in the series Cir­cuit Archi­tec­tures Explored

I’ve now writ­ten six posts, includ­ing this one, on the top­ic of cir­cuit archi­tec­tures for the safety-related parts of con­trol sys­tems. In this post, we’ll com­pare the Inter­na­tion­al and North… 

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Interlock Architectures – Pt. 5: Category 4 – Control Reliable

This entry is part 5 of 8 in the series Cir­cuit Archi­tec­tures Explored

Ed. note: I’ve made a few updates to this art­icle since it was first pub­lished in 2011, with the most recent on 2020-05-11. – DN – The most reli­able of the five… 

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Interlock Architectures – Pt. 4: Category 3 – Control Reliable

Category 3 Architecture Logic Block Diagram
This entry is part 4 of 8 in the series Cir­cuit Archi­tec­tures Explored

This post was updated on 2020-03-28. Cat­egory 3 sys­tem archi­tec­ture is the first cat­egory that could be con­sidered to have sim­il­ar­ity to “Con­trol Reli­able” cir­cuits or sys­tems as was defined in… 

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Understanding Risk Assessment

A group surrounding a computer discussing a problem.
This entry is part 10 of 9 in the series Risk Assess­ment

When people dis­cuss ‘Risk’ there are a lot of dif­fer­ent assump­tions made about what that means. For me, the study of risk and risk assess­ment tech­niques star­ted in 1995. As a technologist… 

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IEC/TR 62061 – 1 Reviewed

This entry is part 2 of 2 in the series IEC/TR 62061 – 1

Why You Need to Spend More Cash on Yet Anoth­er Doc­u­ment Stand­ards organ­iz­a­tions pub­lish doc­u­ments in a fairly con­tinu­ous stream, so for those of us tasked with stay­ing cur­rent with a large… 

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Interlock Architectures – Pt. 3: Category 2

ISO 13849-1 Figure 10
This entry is part 3 of 8 in the series Cir­cuit Archi­tec­tures Explored

This art­icle explores the require­ments for safety related con­trol sys­tems meet­ing ISO 13849 – 1 Cat­egory 2 require­ments. “Gotcha!” points in the defin­i­tion are high­lighted to help design­ers avoid this com­mon pitfalls.

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