There's no end to the dangers around us. I recently purchased a spray nozzle for a garden hose, and it had a label saying: "CAUTION: Shock Hazard: Do not spray near electricity. Detach from faucet during freezing weather. This product intended for outdoor watering only. Do not use with water exceeding 38degC or with pressures exceeding 60 psi."
I took it back - I don't feel qualified to use it. Besides, I wanted a spray nozzle to water the plants in my living room. : ) Pat Lawler EMC Engineer SL Power Electronics Corp. [email protected] wrote on 07/31/2009 03:56:10 AM: > I expect shortly someone will need me to affix an A4 paper at my > monitor saying "Monitor screen. Read here what computer tells you." > > Best Regards > Piotr Galka > MicroMade > Poland > > ----- Original Message ----- > From: Flavin, John > To: [email protected] > Sent: Thursday, July 30, 2009 7:56 PM > Subject: Workplace Safety Rules > > I like to know this group's experiences regarding the following, > which has been put into my lap to resolve. > > Our plant manager recently arranged a class on electrical safety > (based on OSHA regulations and the NFPA 70E standard) for our > engineering staff who work in all of our labs. The instructor was > given a tour of our facility, including our Safety and EMI labs > (due to the large size and power requirements of our products, we > have our own safety and EMI labs. Safety testing is witnessed by > a test engineer from an outside lab, which writes the CB reports > for us; our EMI lab is NVLAP accreditted). > > During the course of the class, the instructor showed several > "examples" of items taken from both these labs as possible items > which were "unsafe". For example, he showed a power cord which had a > section of the outer insulation stripped off, so that the individual > insulated conductors were visible, and asked if this was safe. (How > else do you put a current clamp around one conductor in a 3phase, 5 > wire cord?). Our plant manager wanted to know why a 32A pin and > sleeve connector with the appropriate HAR cordage (which we use > when our product is sold in Europe) didn't have 6 gauge UL approved > cordage. Adapters to allow us to connect our EUT to LISNs and CDNs > for EMI testing likewise were suspect. > > There were other examples, but you get the idea. We're not talking > about using wire nuts and duct tape to kludge together some AC > cords to provide 50A service to our product. All these adapters have > been built for a specific purpose, and use the appropriate sized > conductors for the rated current of the plug/connector. > > The class also covered activities which can only be performed by a > "qualified worker" (as defined by OSHA). Examples given were using > a voltmeter to read AC line voltage, or replacing plugs/connectors > on AC mains cords. As we test our products for both domestic (60Hz) > and European (50Hz), we have two large synthetic power sources, and > to avoid destroying very expensive racks of equipment, we routinely > check the AC voltage before we plug in our products. Apparently, we > are not qualified to do this. > > I understand our plant manager's concern that OSHA might cite some > of these things as safety violations, which would cost us $$$ to > rectify, and would probably shut down our lab from doing any work > until we satisfy OSHA. His view is that it's not sufficient that > these two labs are restricted access (all of us working in these > labs have been issued numbered, "do not duplicate" keys), but that > there must be detailed instructions for the use of every item, and > for every type of measurement we make, and that any of this > equipment should be locked away within these locked labs (which is a > non-trivial issue for our EMI lab). He argued that these types of > things are the proverbial "attractive nuisance", prone to abuse. > > My questions are > > 1) If an OSHA inspector were to visit an EMI or safety lab, would > he be sufficiently knowledgeable as to what type of work is > normally done there, or would he essentially "go by the book", and > if it isn't in the NEC or NFPA, it's bad? Does anyone have any > experience (good or bad) with this? > > 2) The thought of having to write, in excruciating detail, a > procedure for every conceivable type of measurement we make, or > could make hardly seems a productive use of my time, considering > that the intended audience are already well versed in these > practices, and that I couldn't possibly cover the universe of > measurements we may do in the future. As part of our EMI lab > training, we make a general statement that lab personnel shall be > capable of using lab equipment such as voltmeters, current probes, > oscilloscopes, spectrum analyzers etc. for debugging, which implies > knowing how to use them to make appropriate measurements. Is this > good enough? What level of detail is appropriate? What do other > labs do to address this? > > John D. Flavin > Teradata TCP Engineering > 17095 Via del Campo > San Diego, CA 92127 > [email protected] > V: (858) 485-3874 > F: (213) 337-5432 > - > ---------------------------------------------------------------- > 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.ieeecommunities.org/emc-pstc > Graphics (in well-used formats), large files, etc. can be posted to > that URL. > > Website: http://www.ieee-pses.org/ > Instructions: http://listserv.ieee.org/request/user-guide.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.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.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]>
