Technical articles

We offer a selection of technical articles dealing with the safety of machines and plants - both in general and on particular aspects of product families for machine safety. Some of the contributions are from Schmersal employees, others are written by independent specialists, e.g. from industrial assessment organisations. Download the PDFs.

  • Minimum Distances for Safety Control Measures

    cover of Executive Summary of webinar: Minimum Distances for Safety Control Measures

    The executive summary from our webinar [more]

    Fixed guards and presence sensing safety devices are often used as control measures for risk reductions. Discover the crucial factors behind implementing these measures - particularly the considerations for their strategic placement to ensure compliance and effectiveness in risk reduction. In this webinar you will master the art of calculating and implementing minimum safe distances. 


    > Download the summary

    > View the webinar (1 hour)


  • Applying ISO 13849 Functional Safety to Machines in the USA

    cover of executive summary for ISO13849 Webinar

    The executive summary from our webinar [more]

    Functional safety and Performance Levels are key elements behind the global-harmonized machine safety standard ISO 13849. This webinar provided an overview of the standard, when and how to use it, how it relates to machine safety in the USA and a look at misconceptions surrounding the standard. 


    > Download the summary

    > View the webinar (1 hour)


  • Control Categories according to ISO 13849

    The term “Category” is often used in safety standards to describe a specific function or level of reliability. [more]

    ISO 13849 Safety of machinery — Safety-related parts of control systems uses the term category to designate 5 different wiring schemes available for a safety circuit. This paper briefly explains these categories.


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  • SAFER Workplace

    Cover of SAFER Workplace article

    The SAFER Workplace initiative promotes workplace safety to reduce the potential of near misses, accidents, and injuries.  [more]

    The SAFER acronym is based on the 5 fundamental steps used to conduct a risk assessment and stands for STOP, ASSESS, FORMULATE, EXECUTE, and REVIEW. These steps are fundamental to properly addressing any concerns such as unsafe operations of machinery so that a safe and efficient solution can be created and implemented.

    > Download the article

    > National SAFER Workplace Day - June 30, 2023


  • Commonly Overlooked And Misapplied Machine Safety Requirements

    Cover of executive suammry of webinar - Commonly Overlooked & Misapplied Machine Safety Requirements

    The executive summary from our webinar [more]

    With so many safety aspects to consider, it is easy to overlook crucial elements to successfully implement a safety measure.  Some commonly overlooked and misapplied machine safety requirements: Risk Assessment, Stop Time Measurements, Misapplied Mechanical Switches, Implementing Safety Categories, Series Connection for High-Risk Applications, and The Misconception of Collaborative Robots.

    > Download the summary

    > View the webinar (1 hour)


  • Safeguarding Robots and Robot Cells

    image of title page for Safeguarding Robots and Robot Cells

    Protect personnel working directly with or around robots. [more]

    Learn which standards are relevant for robot applications, understand robot functionality and limitations and how they affect typical methods of safeguarding robots, and review safety considerations for Collaborative Robots.


    > Download the article



  • How To Create An Effective Machine Safety Training

    cover-executive summary of Training webinar

    The executive summary from our webinar [more]

    Is there a right way to present machine safety? Safety training often gets the bad reputation of being dull, making the process ineffectual. Learn effective ways to avoid the boredom and integrate training into your machine safety mindset.


    > Download the summary

    > View the webinar (1 hour)


  • Case Study: Practical Safety Solution For Setup Mode

    Safety Evaluation Of A Redundant Rotary Encoder With Use Of A Safety Mini Controller [more]

    For setup mode or troubleshooting on machinery, the ‘Safely limited speed with opened guard door’ safety function is extremely relevant. This case study from Schmersal and Wachendorff presents an example safety solution involving a redundant rotary encoder and a safety controller and evaluates the solution in accordance with EN ISO 13849.


    > Download the Case Study


  • Validation In Accordance With ISO 13849-2

    screenshot of article - Validation

    An important standard which gets too little attention [more]

    ISO 13849 part 2 defines the validation process for the safety functions incorporated into the machine. This article summarizes the standard, indicating who should perform validations, the steps of the process, and the benefits of performing this vital step in the design process.

    Excerpt from mrl news / issue 2019.01pages 6 & 7


    > Download the article


  • Why Machine Safety Is Not Complete Without Validation

    cover of Executive Summary - Validation

    The executive summary from our webinar [more]

    When a machine is upgraded to meet the requirements issued by a machine safety risk assessment, the system needs to be tested to ensure it functions as intended. This executive summary of our recent webinar examines why Validation is needed to ensure we are designing, installing, and testing safety systems correctly, along with the steps associated with completing a successful Validation.

    > Download the summary

    > View the webinar (1 hour)


  • FAQ - Safety Risk Assessment Guidelines for Automation Equipment

    first page of the FAQ - risk assessment

    Questions and answers on risk assessment [more]

    Risk assessments are the starting point to any machine safeguarding initiative, for any automated machines, even industrial robot and inherently safe by design collaborative robots. This Frequently Asked Questions (FAQ) covers the basics of risk assessments, including the goals of the assessment, gathering the right team to perform them, and several methodologies to use.


    > Download the article


  • Selection Guidelines For Safety Light Curtains

    First page of the SLC Selection guideline article

    The four main options to consider in selecting the right Safety Light Curtain for your application. [more]

    Safety light curtains are a viable safeguarding option for point of operation or perimeter guarding. Choosing the right one is not terribly complicated, once a thorough risk assessment is performed.  It helps to define the Type, Resolution, Protection field, and Special operation modes needed for your application.


    > Download the article


  • Risk Assessment Methods For Machine Safety And Cobots

    Cover image of the executive summary for Risk Assessment Methods

    The executive summary from our webinar [more]

    Risk assessments are the starting point to any machine safeguarding initiative. Identifying the risks is the first step to abating them. But many individuals rely on their understanding of what equipment requires risk assessment or use a company standard that may not follow current applicable standards. This executive summary of our recent webinar explains methods for creating a risk assessment program for all EHS, engineering design, and maintenance staff in your company.

    Download the summary

    View the webinar (1 hour)


  • Sanitary And Hygienic Design Standards

    An overview of US and Canadian standards for food industry [more]

    Hygiene and sanitation are key issues in the food processing industry to prevent food borne illnesses. It influences the design of machines used in areas that need to be constantly cleaned. It is important when selecting safety devices or command devices for food processing machines that they meet hygienic or sanitary standards.

    Download the article

  • Building A Machine Safety Mindset

    The executive summary from our webinar [more]

    Many individuals involved in machine safety design rely on their understanding of “what is safe” when designing or upgrading an industrial machine. This can lead to inconsistent machine safety methodologies amongst EHS, Engineering design, and maintenance professionals in a workplace. This executive summary of our recent webinar discusses the steps of building a machine safety mindset to achieve a more uniform company machine guarding and safety methodology.


    Download the summary


    View the webinar (1 hour)


  • Challenges In Machine Safeguarding

    The executive summary from our webinar [more]

    Companies understand that employee safety is critical. No business wants its workers to get injured. Despite this understanding, companies still seem to come up with numerous reasons why they can’t implement the very machine safeguarding solutions that would keep their employees safe. The challenges to machine safeguarding are significant, but these challenges can be overcome with proper education, good risk assessments, and solutions that are developed and implemented to meet the specific business need.


    Download the summary


    View the webinar (1 hour)


  • FAQ - How To Safeguard Your Robots and Robot Cells

    Questions and answers on robot safeguarding [more]

    More and more robots are being introduced and utilized for industrial automation. From the traditional industrial robot to modern technology with collaborative robots, challenges arise to have people work safely on robots and in or around robot cells. Learn more about how to properly safeguard robots and robot cells in this Frequently Asked Questions (FAQ).

    Download the article

  • The Effect Of Industry 4.0

    Efficiently Increase Production While Improving Safety [more]

    We are in the midst of the 4th Industrial Revolution which aims to combine cutting edge technology with rigorous safety requirements. This article discusses the goals of Industry 4.0 and the path taken to arrive at this groundbreaking transformation of the modern industrial factory.


    Download the article

  • The Future Of The Industrial Robot

    What the acceptance of inherently safe Collaborative Robots means for the traditional Industrial Robot [more]

    Robots which work “hand in hand” with humans have now found their place safely on to the factory floor. This article discusses the growing acceptance of these collaborative robots, their safety requirements, and how it might affect the use of traditional industrial robots.


    Download the article

  • Food Safety Modernization Act (USA)

    Equipment and Control Designs for FSMA [more]

    The new Food Safety Modernization Act legislation demands stricter proactive measures to prevent hazards that could affect food within that facility. One of those measures deals with the hygienic designs of the equipment and controls.

    Download the article here

  • Calculating Safety Distances

    Requirements for the proper placement of safety guards and presence sensing devices [more]

    Applying safeguards to equipment and machines may lead to a false sense of safety if not applied correctly. This paper explores the often overlooked practice of determining the minimum safe distance or height at which a hard guard or protective device should be installed.


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  • Fault Masking

    The article discusses a potential problem with the practice of wiring safety devices in series: [more]

    "Daisy chaining" may mask faults in the system due to accumulation of faults that may compromise safety. It defines the problem and provides several solutions for overcoming it.


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  • Machine Guarding and Lock Out / Tag Out

    This paper provides some insight as to the differences between the two methods of safely controlling hazardous energy. [more]

    It provides the guidelines for when and why to use LO/TO on some tasks and machine guarding on other tasks.

  • Locking Devices for Machine Safeguarding

    This paper looks at the principles behind Guard Locking and Process Locking of safety interlocks. [more]

    It provides several examples when to use each method, and describes the locking principles and lock release types defined by the ISO 14119 standard for guard interlock design and selection.

  • Efficiency in Machine Safety

    This paper looks at the growing trend of designing safety systems to meet the efficiency requirements of other machine control systems. [more]

    It provides several examples of systems currently being used such as electronic switches and AS-Interface.

  • Safeguarding 101

    This article looks at OSHA regulations and relevant consensus standards [more]

    to help you determine what needs to be guarded, to what degree, and what type of devices can be used.

  • Emergency Stop Devices: More Than An Off Switch

    Emergency Stop (E-Stop) buttons should be the most identifiable element on a machine and serve a specific function which is universally known. [more]

    But they are often misunderstood and misused. This article explores the requirements for E-Stops.

  • Principles for Design and Selection of Interlocking Devices

    A summary of the focal points specified by the new ISO 14119 standard [more]

    which regulates the design and use of interlocking devices and the changes that design engineers in mechanical engineering can expect.

  • Machine Safety Standards

    An introduction to various safety standards that apply to machine safety in the US, Canada, and Europe.


  • Safety Controller Selection Guidelines

    Choosing an appropriate safety controller is vital to the safety of the machine. [more]

    Safety controllers increase the reliability of the machine guarding safety system. Some form of a safety controller is required to meet higher risk categories and to meet the requirements for Control Reliability. This article discusses the importance of choosing an appropriate safety controller and highlights several selection criteria.


    Download the article






Context Column

Fact Sheet

In the demanding field of machine safety the Schmersal Group is one of the international market and competence leaders. Based on more than 18,000 different switching devices the corporate group offers system solutions for the safety of man and machine.

The company is represented by seven manufacturing sites on three continents and with its own subsidiaries and sales partners in more than 60 nations.

Download Fact Sheet, en (pdf)

Download Fact Sheet, de (pdf)