Hi Scott, The people who sit on CENELEC committees are humans and they are prone to human errors. They write standards in plain language that is easy to understand. The problem comes when these standards are adopted into law. Laws that are very precise are easy to interpret, but are very complicated. Take the Low Voltage Directive as an example. It tells us that products must be safe, but doesn't give much more detail. If that were the only regulation in place, we would need armies of lawyers to argue whether specific products are acceptably safe or have unreasonable hazards. We are given the option of complying with standards that give us more detail on one route to compliance. If you have an IT product that meets EN 60950-1, you have met one legal interpretation of acceptably safe.
In addition, standards are written by committee. The words need to be acceptable to a specified majority of the committee before the standard can be adopted. Precise language can be harder to pass sometimes because some committee members may object to one particular item. The whole committee may agree on the general intent of the standard but not every specific item. A more general wording can be easier to pass. The CENELEC audio requirements have three tests to determine if a product is within the scope. The product is within the scope if: − is designed to allow the user to listen to recorded or broadcast sound or video; and − primarily uses headphones or earphones that can be worn in or on or around the ears; and − allows the user to walk around while in use. Let's take the example of a portable DVD player. It meets the first clause as playing recorded video is its primary function. Many meet the second clause having headphone jacks, and often multiple headphone jacks. The third test is the one that I would consider to broadly written. A portable DVD player allows the user to walk around while in use. It is light enough to hold in your hands and it is battery powered. However, that isn't the intended use nor is it a likely use. It is difficult to walk any distance while concentrating on the screen to watch a movie. Good legal council will be able to help you determine what the intent of the standard is. This may require figuring out what the intent of the standards committee was. This may require research into CENELEC OSM decision, committee notes and such. A lawyer knows how the law is applied and the lawyer can best determine how to use that application of the law to see if your product is within the scope of the standard. When a standard is written with broad text, different courts may interpret it different ways. A lawyer may be better suited to telling you how a court will interpret the standard. The standard writers may not have intended to write clauses that require interpretation, but the law is enforced by courts, not engineers. IEC 62368-1 addresses this issue by changing the third test of the requirement. It states that the product is within the scope if it "is body worn (of a size suitable to be carried in a clothing pocket) and is intended for the user to walk around with while in use." The size of a clothing pocket is still up to interpretation, but this clause is a bit more specific than the text written by CENELEC. It's easier for me to argue that a portable DVD player is too large to fit into a typical clothing pocket and it certainly can't be used for its primary function while in a pocket. There is still reason to consult an attorney for some products, but not as many. In this case, the ambiguity largely comes down to what is pocket sized. A tablet computer with a 10 inch screen might not be, and a cell phone with a 4 inch screen likely is within the scope. But we have devices with 5, 6, 7 and 8 inch screens. Where is the line where something is too big to fit in a pocket? TC108 was well m! eaning in trying to craft the scope, but you still have a standard that may be adopted into national law in various countries. If so, courts, regulators and lawyers will be called on to determine what is pocket sized. Regards, Ted Eckert Compliance Engineer Microsoft Corporation ted.eck...@microsoft.com The opinions expressed are my own and do not necessarily reflect those of my employer. -----Original Message----- From: Scott Xe [mailto:scott...@gmail.com] Sent: Tuesday, February 05, 2013 6:19 AM To: Ted Eckert; EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: EN 60065 A12 - Sound Pressure Restriction Hi Ted, Thanks for your opinion. The excessive sound pressure issue occurred since Sony Walkman era and taken up by Apple iPods in last few years. The issue was discussed/debated many years ago and concluded a standard for compliance. Both will harm our human ears at high sound level regardless of analogue devices or digital devices. In the past, Apple iPods could not run 10 hours per single charge of battery pack using micro drive while Sony MP3 players was able to play music for 52 hrs per single charge of battery pack. On the latest versions, it is easily to achieve long hour playback. It is a very valid point for digital devices that employ the firmware for controlling the functionality and features. Adding the instructional safeguard is deadly easy to accomplish. I guess the standard working committee does not want to control analogue devices since there would be a strong reaction. They also believe even they are not controlling them, they are going to phasing out soon. Music files will replace CDs, DVDs or even BDs. HMV closing down in the UK is a good trend indicator. Is there any particular reason for EN standards that are written with the aid of attorney to understand? Most of readers are normal engineers and they find difficult in understanding/interpreting the standard easily and correctly. Do they have any mechanism to help the engineers to use the standard correctly? Regards, Scott On 5/2/13 5:38 AM, "Ted Eckert" <ted.eck...@microsoft.com> wrote: > Hello Scott, > > I believe that there are at least two reasons analog music players are > exempted. The first is that the instructional safeguard in the > standard is to provide a specific notification to the user when they > exceed 85 dBA. This is not practical on a purely analog device. The > instructional safeguard must be repeated for every 20 hours > cumulative listening above 85 dB, and an analog device cannot easily > make this measurement. Second, analog devices such as a portable > cassette tape player are not practical to use for extended periods. A > user who wanted to listen to 10 hours of continuous music would need > to carry around quite a few cassette tapes or would have to listen to the > same tape over and over. > > I believe that portable CD players are within the scope of the requirement. > However, a portable DVD player that includes a screen is different > from a CD play. Although it is technically possible to walk around > with a DVD player while watching a movie, it is neither practical nor > a normal use. However, I am not qualified to say with certainty > whether a portable DVD player is exempted. It is possible that you can > make a reasonable argument that a portable DVD player would not fit > within the scope. However, that will depend on the design and features of the > DVD player. > > It may be best to consult an attorney who is familiar with the > regulations to determine if a particular product is within or outside of the > scope. > > Regards, > Ted Eckert > Compliance Engineer > Microsoft Corporation > ted.eck...@microsoft.com > > The opinions expressed are my own and do not necessarily reflect those > of my employer. > > > > -----Original Message----- > From: Scott Xe [mailto:scott...@gmail.com] > Sent: Monday, February 04, 2013 8:15 AM > To: EMC-PSTC@LISTSERV.IEEE.ORG > Subject: EN 60065 A12 - Sound Pressure Restriction > > Dear Sir/Madam, > > In this requirement, there is a following exemption. > > € analogue personal music players (personal music players without any > kind of digital processing of the sound signal) that are brought to > the market before the end of 2015. > > NOTE 4 > > This exemption has been allowed because this technology is falling out > of use and it is expected that within a few years it will no longer > exist. This exemption will not be extended to other technologies. > > I believe the old design portable DVD players with a pair of earphones > and operated on batteries or rechargeable batteries are qualified for > such exemption. I am seeking advice why the digital processing of > sound signal is so critical to this sound pressure restriction and how > to identify if the digital processing is built in the unit or not. > > Thanks and regards, > > Scott > > - > ---------------------------------------------------------------- > 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 <emc-p...@ieee.org> > > 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://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 <emcp...@radiusnorth.net> Mike Cantwell > <mcantw...@ieee.org> > > For policy questions, send mail to: > Jim Bacher: <j.bac...@ieee.org> > David Heald: <dhe...@gmail.com> > > - ---------------------------------------------------------------- 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 <emc-p...@ieee.org> 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://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 <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>