Re: A little off topic but ... exploding CD's ???
Sounds to me like someone has too much time on their hands. On the face of it, it is amusing, but it is this kind perceived hazard that safety agencies and lawyers love, with the result that ridiculous requirements like this start appearing in safety standards. Maybe we should just ban all electrical and mechanical devices, along with large bodies of water so that people don't drown etc. Regards Doug Beckwith Doug McKean dmck...@corp.auspex.com@majordomo.ieee.org on 05/09/2002 06:34:09 PM Please respond to Doug McKean dmck...@corp.auspex.com Sent by: owner-emc-p...@majordomo.ieee.org To: EMC-PSTC Discussion Group emc-p...@majordomo.ieee.org cc: Subject: A little off topic but ... exploding CD's ??? As a matter of safety, has anyone really addressed the issue of the upper speed limit of CDs? Quoted from the following webpage ... http://www.qedata.se/e_js_n-cdrom.htm Introduction But where's the limit? Manufacturers try to outspin each other all the time by selling CD-ROM drives with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, 16x, 32x, 56x and 64x come in a never ending stream. The CD is forced to rotate faster and faster. At what speed will a CD blow up, and can you do something to prevent it from exploding? ... At the conclusion of the test, the author recommends the following ... Safety Recommendations The committee wishes, after finishing its work, to suggest the following safety precautions. Safe distance to a CD-ROM drive with spin ratio 64x CLV should be no less than 5 metres (15 ft.). All work with CD-ROM units should require safety goggles and protective clothing be worn. CD-ROM drives of the 64x CLV class and higher, should be provided with shrapnel protection of no less than 3 mm aluminium or 1 mm steel. To avoid operator inhalation of CD-ROM particles, CD-ROM drives should be provided with a dust suction fan with suitable filter, or have the fan duct connected directly to the outside air. In addition to the laser light warning label, CD drives should be affixed with another label warning against the hazard of shrapnel, such as the one below: With appropriate labels for exploding CDs. No. This isn't a joke. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: A little off topic but ... exploding CD's ???
I have design speed and phase controllers for small systems running at 64 krpm (IR scanner) that used low pressure Helium to reduce drag and to operate 'air' bearings. Some of the big problems in cars are going up-hill and running into ditches (gyroscopic effects) and what happen to that energy during an accident. That's what scares me. Best regards Gregg PLEASE NOTE: We are currently experiencing serious problems with our service provider PLEASE reply only to gr...@test4safety.com mailto:gr...@test4safety.com and ignore any reference to pgtv.net, Thank you. --Original Message- -From: owner-emc-p...@majordomo.ieee.org -[mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Chris Maxwell -Sent: Friday, May 10, 2002 8:47 AM -To: Doug McKean; EMC-PSTC Discussion Group -Subject: RE: A little off topic but ... exploding CD's ??? - - - -I hope that I don't lead the thread off on a tangent...but a -similar problem is being encountered by those who envision -magnetically levitated flywheel powered electric cars. (By -the way, the flywheel is levitated, not the car) - -A well designed flywheel system can store electricity with a -better weight to energy ratio of currently available batteries...But. - -In order to do so with a lightweight flywheel (about 50 -pounds); the flywheel needs to spin up to something like -100,000 rpm. They are testing composite materials (graphite, -kevlar...) and the testing has led to some spectacular -failures with shredded flywheel all over the place. - -The other problem is...how do you contain these babies if the -car has an accident. Just imagine a wreck that produces a -bunch of 50lb buzz saws bouncing around the intersection...it -wouldn't be pretty. - -As far as CD's...maybe everyone should just listen to George -Jones... or something else that is slow enough to keep he -speed safe :-) - -Chris Maxwell | Design Engineer - Optical Division -email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 -315 797 8024 - -NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA -web www.nettest.com | tel +1 315 797 4449 | - - - - - -Original Message- - From:Doug McKean [SMTP:dmck...@corp.auspex.com] - Sent:Thursday, May 09, 2002 6:34 PM - To: EMC-PSTC Discussion Group - Subject: A little off topic but ... exploding CD's ??? - - - As a matter of safety, has anyone really addressed - the issue of the upper speed limit of CDs? - - Quoted from the following webpage ... - http://www.qedata.se/e_js_n-cdrom.htm - - Introduction But where's the limit? Manufacturers try to - outspin each other all the time by selling CD-ROM drives - with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, - 16x, 32x, 56x and 64x come in a never ending stream. The - CD is forced to rotate faster and faster. At what speed will - a CD blow up, and can you do something to prevent it from - exploding? ... - - At the conclusion of the test, the author recommends the - following ... - - Safety Recommendations The committee wishes, after finishing - its work, to suggest the following safety precautions. - - Safe distance to a CD-ROM drive with spin ratio 64x CLV - should be no less than 5 metres (15 ft.). - - All work with CD-ROM units should require safety goggles and - protective clothing be worn. - - CD-ROM drives of the 64x CLV class and higher, should be - provided with shrapnel protection of no less than 3 mm aluminium - or 1 mm steel. - - To avoid operator inhalation of CD-ROM particles, CD-ROM - drives should be provided with a dust suction fan with suitable - filter, or have the fan duct connected directly to the outside air. - In addition to the laser light warning label, CD drives should be - affixed with another label warning against the hazard of shrapnel, - such as the one below: - - With appropriate labels for exploding CDs. - No. This isn't a joke. - - Regards, Doug McKean - - - - --- - This message is from the IEEE EMC Society Product Safety - Technical Committee emc-pstc discussion list. - - Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ - - To cancel your subscription, send mail to: - majord...@ieee.org - with the single line: - unsubscribe emc-pstc - - For help, send mail to the list administrators: - Ron Pickard: emc-p...@hypercom.com - Dave Heald: davehe...@attbi.com - - For policy questions, send mail to: - Richard Nute: ri...@ieee.org - Jim Bacher: j.bac...@ieee.org - - All emc-pstc postings are archived and searchable on the web at: - http://ieeepstc.mindcruiser.com/ - Click on browse and then emc-pstc mailing list - -This message is from the IEEE EMC Society Product Safety -Technical Committee emc-pstc discussion list. - -Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc
RE: A little off topic but ... exploding CD's ???
Going around corners presents another interesting problem, depending on the orientation of its axis. The vacuum chamber that such a flywheel must operate in (to make it practical) presents another interesting challenge. Bob Wilson TIR Systems Ltd. Vancouver. -Original Message- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: May 10, 2002 5:47 AM To: Doug McKean; EMC-PSTC Discussion Group Subject: RE: A little off topic but ... exploding CD's ??? I hope that I don't lead the thread off on a tangent...but a similar problem is being encountered by those who envision magnetically levitated flywheel powered electric cars. (By the way, the flywheel is levitated, not the car) A well designed flywheel system can store electricity with a better weight to energy ratio of currently available batteries...But. In order to do so with a lightweight flywheel (about 50 pounds); the flywheel needs to spin up to something like 100,000 rpm. They are testing composite materials (graphite, kevlar...) and the testing has led to some spectacular failures with shredded flywheel all over the place. The other problem is...how do you contain these babies if the car has an accident. Just imagine a wreck that produces a bunch of 50lb buzz saws bouncing around the intersection...it wouldn't be pretty. As far as CD's...maybe everyone should just listen to George Jones... or something else that is slow enough to keep he speed safe :-) Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: A little off topic but ... exploding CD's ???
I hope that I don't lead the thread off on a tangent...but a similar problem is being encountered by those who envision magnetically levitated flywheel powered electric cars. (By the way, the flywheel is levitated, not the car) A well designed flywheel system can store electricity with a better weight to energy ratio of currently available batteries...But. In order to do so with a lightweight flywheel (about 50 pounds); the flywheel needs to spin up to something like 100,000 rpm. They are testing composite materials (graphite, kevlar...) and the testing has led to some spectacular failures with shredded flywheel all over the place. The other problem is...how do you contain these babies if the car has an accident. Just imagine a wreck that produces a bunch of 50lb buzz saws bouncing around the intersection...it wouldn't be pretty. As far as CD's...maybe everyone should just listen to George Jones... or something else that is slow enough to keep he speed safe :-) Chris Maxwell | Design Engineer - Optical Division email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797 8024 NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA web www.nettest.com | tel +1 315 797 4449 | -Original Message- From: Doug McKean [SMTP:dmck...@corp.auspex.com] Sent: Thursday, May 09, 2002 6:34 PM To: EMC-PSTC Discussion Group Subject: A little off topic but ... exploding CD's ??? As a matter of safety, has anyone really addressed the issue of the upper speed limit of CDs? Quoted from the following webpage ... http://www.qedata.se/e_js_n-cdrom.htm Introduction But where's the limit? Manufacturers try to outspin each other all the time by selling CD-ROM drives with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, 16x, 32x, 56x and 64x come in a never ending stream. The CD is forced to rotate faster and faster. At what speed will a CD blow up, and can you do something to prevent it from exploding? ... At the conclusion of the test, the author recommends the following ... Safety Recommendations The committee wishes, after finishing its work, to suggest the following safety precautions. Safe distance to a CD-ROM drive with spin ratio 64x CLV should be no less than 5 metres (15 ft.). All work with CD-ROM units should require safety goggles and protective clothing be worn. CD-ROM drives of the 64x CLV class and higher, should be provided with shrapnel protection of no less than 3 mm aluminium or 1 mm steel. To avoid operator inhalation of CD-ROM particles, CD-ROM drives should be provided with a dust suction fan with suitable filter, or have the fan duct connected directly to the outside air. In addition to the laser light warning label, CD drives should be affixed with another label warning against the hazard of shrapnel, such as the one below: With appropriate labels for exploding CDs. No. This isn't a joke. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: A little off topic but ... exploding CD's ???
No need to worry. First, a CD can be spun at many tens of thousands of RPM without destruction. But more importantly, the spin ratios are not straight multiples of the basic disk RPM. After all, if this were true, the 300 to 400 RPM maximum speed of a 1X CD player, would be 19,000 to 25,600 RPM, and 64X CD-ROMs do NOT rotate that fast. Much of the increase a 64X CD-ROM is claiming, is due to reading ahead and buffering, so that in normal intermittent use, the apparent transfer rate is (supposedly) 64X normal. This is why tests show that, when large amounts of data are being read, these drives cannot get anything close to their claimed data transfer rate. This is why one cannot read an entire audio CD into memory as a raw WAVE file, at anything close to the claimed rate. Bob Wilson TIR Systems Ltd. Vancouver. -Original Message- From: Doug McKean [mailto:dmck...@corp.auspex.com] Sent: May 9, 2002 3:34 PM To: EMC-PSTC Discussion Group Subject: A little off topic but ... exploding CD's ??? As a matter of safety, has anyone really addressed the issue of the upper speed limit of CDs? Quoted from the following webpage ... http://www.qedata.se/e_js_n-cdrom.htm Introduction But where's the limit? Manufacturers try to outspin each other all the time by selling CD-ROM drives with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, 16x, 32x, 56x and 64x come in a never ending stream. The CD is forced to rotate faster and faster. At what speed will a CD blow up, and can you do something to prevent it from exploding? ... At the conclusion of the test, the author recommends the following ... Safety Recommendations The committee wishes, after finishing its work, to suggest the following safety precautions. Safe distance to a CD-ROM drive with spin ratio 64x CLV should be no less than 5 metres (15 ft.). All work with CD-ROM units should require safety goggles and protective clothing be worn. CD-ROM drives of the 64x CLV class and higher, should be provided with shrapnel protection of no less than 3 mm aluminium or 1 mm steel. To avoid operator inhalation of CD-ROM particles, CD-ROM drives should be provided with a dust suction fan with suitable filter, or have the fan duct connected directly to the outside air. In addition to the laser light warning label, CD drives should be affixed with another label warning against the hazard of shrapnel, such as the one below: With appropriate labels for exploding CDs. No. This isn't a joke. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
RE: A little off topic but ... exploding CD's ???
Reminds me of an article I read some years ago, where an engineer was reminiscing about the early days of hard disk drive development. IBM was the company, I think. Anyway, when the absolutely beautiful and impressive testbed was fired up and began to run, the nearly room-sized piece of equipment began to go South quickly. Your reference to exploding CD-ROMs brought back images of an out of control spinning platter, several feet wide, breaking out of the confines of its machine and flying around the room while engineers dove for cover. I loved that story. Chet Summers Pelco -Original Message- From: Doug McKean [mailto:dmck...@corp.auspex.com] Sent: Thursday, May 09, 2002 3:34 PM To: EMC-PSTC Discussion Group Subject: A little off topic but ... exploding CD's ??? As a matter of safety, has anyone really addressed the issue of the upper speed limit of CDs? Quoted from the following webpage ... http://www.qedata.se/e_js_n-cdrom.htm Introduction But where's the limit? Manufacturers try to outspin each other all the time by selling CD-ROM drives with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, 16x, 32x, 56x and 64x come in a never ending stream. The CD is forced to rotate faster and faster. At what speed will a CD blow up, and can you do something to prevent it from exploding? ... At the conclusion of the test, the author recommends the following ... Safety Recommendations The committee wishes, after finishing its work, to suggest the following safety precautions. Safe distance to a CD-ROM drive with spin ratio 64x CLV should be no less than 5 metres (15 ft.). All work with CD-ROM units should require safety goggles and protective clothing be worn. CD-ROM drives of the 64x CLV class and higher, should be provided with shrapnel protection of no less than 3 mm aluminium or 1 mm steel. To avoid operator inhalation of CD-ROM particles, CD-ROM drives should be provided with a dust suction fan with suitable filter, or have the fan duct connected directly to the outside air. In addition to the laser light warning label, CD drives should be affixed with another label warning against the hazard of shrapnel, such as the one below: With appropriate labels for exploding CDs. No. This isn't a joke. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
A little off topic but ... exploding CD's ???
As a matter of safety, has anyone really addressed the issue of the upper speed limit of CDs? Quoted from the following webpage ... http://www.qedata.se/e_js_n-cdrom.htm Introduction But where's the limit? Manufacturers try to outspin each other all the time by selling CD-ROM drives with higher and higher spin ratios. Spin ratios of 2x, 4x, 8x, 16x, 32x, 56x and 64x come in a never ending stream. The CD is forced to rotate faster and faster. At what speed will a CD blow up, and can you do something to prevent it from exploding? ... At the conclusion of the test, the author recommends the following ... Safety Recommendations The committee wishes, after finishing its work, to suggest the following safety precautions. Safe distance to a CD-ROM drive with spin ratio 64x CLV should be no less than 5 metres (15 ft.). All work with CD-ROM units should require safety goggles and protective clothing be worn. CD-ROM drives of the 64x CLV class and higher, should be provided with shrapnel protection of no less than 3 mm aluminium or 1 mm steel. To avoid operator inhalation of CD-ROM particles, CD-ROM drives should be provided with a dust suction fan with suitable filter, or have the fan duct connected directly to the outside air. In addition to the laser light warning label, CD drives should be affixed with another label warning against the hazard of shrapnel, such as the one below: With appropriate labels for exploding CDs. No. This isn't a joke. Regards, Doug McKean --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
