Thanks. Very Helpful. The Other Brian
On Wed, Apr 24, 2019 at 1:16 PM Doug Nix, C.E.T. <[email protected]> wrote: > Hi Brian, > > I’ve dealt with many related questions on my blog, machinerysafety101.com > https://machinerysafety101.com/series/emergency-stop/, but not these > specific questions, so I’ll answer them now. Then I’ll add them to the blog > (thanks for the inspiration!). > > 1) How mushroom-shaped is enough? > > There’s no hard answer to this, but I can say this: there are three > fundamental shapes for push button operators, flush, extended, and > mushroom. The intent is that neither flush nor extended head operators be > used for e-stop functions. More info in IEC 60947 on that. > > 2) Yellow background. Yellow backgrounds have to be big enough to provide > clear contrast with the red button operator. A tiny ring, or just a yellow > stripe around the base of the button is not enough in my opinion. Typical > rings are 2x the operator nominal size, i.e., 30 mm buttons get a 60 mm > ring, 22 mm buttons get a 44 mm ring. These are common practice > recommendations. > > 3) Printing “emergency stop” on the yellow ring is not required in any > jurisdiction anymore, and has been removed from NFPA 79, as well as IEC > 60204-1. Just leave it off, as the red/yellow combination is > internationally recognized as the sign for e-stop and emergency switching > off devices. > > Best, > Doug Nix > > [email protected] > Mobile: (519) 729-5704 > Office:(519) 650-4753 > > On Apr 24, 2019, at 12:49, John Woodgate <[email protected]> wrote: > > Mushrooms come in all sorts of shape, so the description is not very > scientific. It's only a concern if the AHJ thinks it is! > > Whether the English is acceptable is a matter for national legislation, so > there are probably several incompatible answers. > > Best wishes > John Woodgate OOO-Own Opinions Only > J M Woodgate and Associates www.woodjohn.uk > Rayleigh, Essex UK > > On 2019-04-24 17:43, Brian Kunde wrote: > > I am constantly being asked three questions about E-Stops which I cannot > find the answers to. > > 1. "Mushroom Shape" is specifically called out in some standards but the > newer style e-stop switches are becoming less and less Mushroom Shaped. If > this a concern? > > 2. "Yellow Background" is getting smaller and smaller. Some small e-stop > switches has no yellow background but has a small area on the shaft of the > switch that is yellow. This is not technically the "background". Is this > acceptable or is a yellow background required in addition? The size of the > yellow area is not specified as far as I have found. > > 3. English text "Emergency Stop" printed on the button or on the yellow > background ring: Is this a problem in non-english speaking countries? Do > I have to translate (like in French for France and Canada) or are these > words "globally acceptable"? I have been telling our engineers to choose > e-stop switches and yellow rings without text but some manufacturers only > provide it with the text. > > Thanks to all. > > The Other Brian > - > ---------------------------------------------------------------- > > 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) <http://www.ieee-pses.org/list.html> > 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]> > > - > ---------------------------------------------------------------- > > 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) <http://www.ieee-pses.org/list.html> > 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]> > > - > ---------------------------------------------------------------- > > 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) <http://www.ieee-pses.org/list.html> > 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]> > - ---------------------------------------------------------------- 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]>
