In general I agree with your summary, but there is one point that really sticks badly for me: Use of FMEA/FMECA for risk assessment. In my opinion, this is a fundamental mistake that is often made because the tools have superficial similarity with OHS/machinery/product risk assessment tools. Bear with me here.
Similarities Both RA and FMEA tools use consequence and probability parameters. Both RA and FMEA tools develop a “score” that is intended to represent the magnitude of the analyzed situation. Differences FMEA is intended to analyze the impact on the performance of a function/provision of a feature by the product. It is focused on Failure Modes (that’s in the title). The consequence parameter is not scaled in terms of injury, but in terms of loss or impact on performance. FMEA probability parameters are scaled differently than RA probability parameters. FMEA is inconsistent with the requirements laid down by ISO 12100. RA is focused on injury to people. The consequence parameter (severity of injury) is focused on the injury to people, not loss of function. The outcome of the tool is risk, not likelihood of failure/loss of function. The RA probability parameter is focused on three critical aspects of human interaction with the product: Frequency AND Duration of Exposure, Probability of the Hazardous Event, and the Probability of Avoiding or Limiting Harm. These tools are structured to be consistent with ISO 12100. These may seem inconsequential differences but they are not. IMO use of FMEA/FMECA for human risk assessment is a serious error and one I strongly counsel against making. Doug Nix [email protected] +1 (519) 729-5704 > On 16-Jun-20, at 18:49, Douglas Powell <[email protected]> wrote: > > All, > > Over the past several years, nearly all safety standards have incorporated > Risk Assessment (RA) as a part of their requirements. I did an informal > search and found that the assessment methods are used in a wide range of > disciplines from electrical products to machinery, robotics, safety software > controls, medical equipment, medical procedures, automotive, aerospace, > traffic control and even tree removal in municipalities. It is very clear > that safety professionals worldwide really do like this method and I think it > lends a certain comfort to a safety engineer's angst in marginal situations. > I probably shouldn't say it but in my personal opinion this is a huge CYA > exercise (cover your anatomy) for all involved. > > Usually the product RA goes before construction review, testing and > certification. It is often used to identify areas not covered well by the > body of the standard and where additional testing may be required. Virtually > all standards describing the use of RA mention the scheme found in FMEA/FMECA > of identifying a tasks, operations, or events and assigning numerical values > to the parameters of interest, followed by the product of these values to > identify level of risk. Commonly these parameters are severity, frequency of > exposure, and possibility of avoidance. Today the use of FMEA goes far beyond > design, manufacturing, and processes. > > Often times, a particular standard will say something like "documents that > can be used as guidance for the safety analysis include..." followed by a > short list of standards from IEC, EN, ISO, ANSI, MIL STD and so on. Notable > to me is the use of the word "can" or "may" which implies the user has some > leeway in selecting which document they prefer. Additionally, further > guidance is often given for "active" protection devices and software/firmware > controls for safety function (i.e. safety integrity levels and performance > levels). Once again, using the methodology of FMEA as a way of assigning risk > levels. > > So after all that, here is my question. Given wide-ranging product types and > use models, the long list of risk assessment standards, has anyone produced a > comprehensive list or matrix correlating products to applicable standards? I > believe a list such as this would be very helpful. > > Stay safe and stay frosty all, > > Doug > > -- > > Douglas E Powell > Laporte, Colorado USA > [email protected] <mailto:[email protected]> > http://www.linkedin.com/in/dougp01 <http://www.linkedin.com/in/dougp01> > > > - > ---------------------------------------------------------------- > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to > <[email protected] <mailto:[email protected]>> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > <http://www.ieee-pses.org/emc-pstc.html> > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ > <http://product-compliance.oc.ieee.org/> can be used for graphics (in > well-used formats), large files, etc. > > Website: http://www.ieee-pses.org/ <http://www.ieee-pses.org/> > Instructions: http://www.ieee-pses.org/list.html (including how to > unsubscribe) <http://www.ieee-pses.org/list.html> > List rules: http://www.ieee-pses.org/listrules.html > <http://www.ieee-pses.org/listrules.html> > For help, send mail to the list administrators: > Scott Douglas <[email protected] <mailto:[email protected]>> > Mike Cantwell <[email protected] <mailto:[email protected]>> > > For policy questions, send mail to: > Jim Bacher <[email protected] <mailto:[email protected]>> > David Heald <[email protected] <mailto:[email protected]>> > - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
