Machine Safety: How safe is safe enough?

In machine guarding, how safe is safe enough? Over my 40 years in industry I’ve heard this comment many times. Is this attitude driven by “safety culture” or is it just a product of qualitative risk management? Is this why risk management for machine guarding and functional safety is advancing globally to quantitatively derived engineering and validation?

01/12/2012


JB Titus, CFSEIn machine guarding, how safe is safe enough? Over my 40 years in industry I’ve heard this comment many times. Is this attitude driven by “safety culture” or is it just a product of qualitative risk management? Is this why risk management for machine guarding and functional safety is advancing globally to quantitatively derived engineering and validation?

   No, this blog is not about the new EN ISO 13849-1 and Performance Levels, etc.

   This blog is about other efforts being evaluated, created, and launched with the objective of “creating a more actionable outcome and enhance the ability to achieve a more predictable, sustainable and safe work environment. It also can help risk assessment teams realize that the result of a risk assessment is not necessarily a conclusion that the condition is safe, but rather an acceptance that the condition is safe enough.” This is the conclusion of an article in this month’s Professional Safety magazine written by John M. Piampiano and Steven M. Rizzo. My assessment of their article is that it enhances the existing qualitative risk management techniques illustrated by existing standards like ANSI B11.TR3 and ANSI/ASSE Z690.3 by combining severity and probability estimations for the severity of injury, more through definitions of each injury level, and a new Risk Matrix that looks eerily similar to a risk matrix in the new EN ISO 13849-1.

ASSE article and table enhances the existing qualitative risk management techniques illustrated by existing standards like ANSI B11.TR3 and ANSI/ASSE Z690.3 by combining severity and probability estimations for the severity of injury, with definitions of

   The writers take these concepts a step further in their model by introducing Administrative Controls versus Engineering Controls based on the different levels potential injury. They also help the SH&E professional understand that levels of residual risk will always result at this point and that individual company risk tolerance is the responsibility of company management. In my opinion, this clearly places the decisions for various levels of risk mitigation in the hands of company management. Ironically this approach seems to follow ANSI B11 – 2008, General Safety Requirements Common to ANSI B11 Machines. This standard clearly identifies that final risk level mitigation rests with company management because they make the decisions for risk tolerance, aka residual risk.

   Is this model “safe enough” and how does the result compare to the quantitative requirements of EN ISO 13849-1? Only you can answer this question.   

   Your comments or suggestion are always welcome so please let us know your thoughts. Submit your ideas, experiences, and challenges on this subject in the comments section below. Click on the following text if you don't see a comments box, then scroll down: Machine Safety: How safe is safe enough?

www.asse.org

  Related articles:

How To Integrate Safety

Safe or Safe Enough by John M. Piampiano and Steven M. Rizzo, Professional Safety, Jan., 2012

EN ISO 13849-1, the quantitative approach to machine safety begins with a qualitative process!

Machinery Directive In 4 Days Drops EN 954 and EN ISO 13849-1 Is Fully In Force – What’s Your Impact?

31-Dec-2011 marks the start of mandatory implementation of ISO 13849-1. Are YOU Ready?

Contact: www.jbtitus.com for “Solutions for Machine Safety”.



No comments
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2013 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Leaders Under 40 program features outstanding young people who are making a difference in manufacturing. View the 2013 Leaders here.
The new control room: It's got all the bells and whistles - and alarms, too; Remote maintenance; Specifying VFDs
2014 forecast issue: To serve and to manufacture - Veterans will bring skill and discipline to the plant floor if we can find a way to get them there.
2013 Top Plant: Lincoln Electric Company, Cleveland, Ohio
Case Study Database

Case Study Database

Get more exposure for your case study by uploading it to the Plant Engineering case study database, where end-users can identify relevant solutions and explore what the experts are doing to effectively implement a variety of technology and productivity related projects.

These case studies provide examples of how knowledgeable solution providers have used technology, processes and people to create effective and successful implementations in real-world situations. Case studies can be completed by filling out a simple online form where you can outline the project title, abstract, and full story in 1500 words or less; upload photos, videos and a logo.

Click here to visit the Case Study Database and upload your case study.

Bring focus to PLC programming: 5 things to avoid in putting your system together; Managing the DCS upgrade; PLM upgrade: a step-by-step approach
Balancing the bagging triangle; PID tuning improves process efficiency; Standardizing control room HMIs
Commissioning electrical systems in mission critical facilities; Anticipating the Smart Grid; Mitigating arc flash hazards in medium-voltage switchgear; Comparing generator sizing software

Annual Salary Survey

Participate in the 2013 Salary Survey

In a year when manufacturing continued to lead the economic rebound, it makes sense that plant manager bonuses rebounded. Plant Engineering’s annual Salary Survey shows both wages and bonuses rose in 2012 after a retreat the year before.

Average salary across all job titles for plant floor management rose 3.5% to $95,446, and bonus compensation jumped to $15,162, a 4.2% increase from the 2010 level and double the 2011 total, which showed a sharp drop in bonus.

2012 Salary Survey Analysis

2012 Salary Survey Results

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.