I feel that we are missing the point of Product Safety and trying to over-simplify the issues (please read John Woodgate's excellent reply).
The culture for product safety is totally different to that required for EMC and Functionality testing. Let me answer by giving another example - also real life...... A company designs a motor speed controller rated 250 kVA. It is programmable via an external PC thorough an RS232 port. Question - what standard do we take the Creepage and clearance distance from. ANSWER - EN60950 Reason:- the PC user accepts a certain level of risk when using the PC. That level of risk is defined by EN60950. If the Motor Controller RS232 port does not provide the SAME LEVEL OF PROTECTION (i.e. those defined by EN60950) then the user will be exposed to a higher level of risk. The Product Safety Engineer MUST consider WHAT can go wrong - HOW might it be used - How might it be connected - How can someone be injured - etc. So in our previous example - let's think of a situation where the motor controller might be connected to a computer network and the implications of that. YES there are limits (the poodle in the microwave oven) BUT there are plenty of real life examples where cutting corners - or failing to take into account had serious outcomes. Examples from history Titanic (material failure) Challenger (O-ring failure) Zeebrugge (failure to follow instructions). ALL could have been avoided given 20-20 hindsight This is a fundamental issue and the correct understanding and application of it is the foundation of everything that product safety is about. I believe that it is the role - the duty and the responsibility of Product Safety Engineers to close the odds on those and similar tragedies occurring. Sometimes we will get it wrong - and when we get it right no-one will notice - but I do not see any option. Best regards Gregg -----Original Message----- with a big SNIP ---- From: [email protected] [mailto:[email protected]]On Behalf Of Colgan, Chris Sent: Thursday, September 27, 2001 9:21 AM To: [email protected] Subject: RE: Applying the appropriate ENs I don't understand how testing to a different standard can make a product "safer". If there is a product specific standard, use it. If you are testing a CD Recorder (presumably what you mean by a CDR) then you should use IEC60065. If you want to exceed the requirements of IEC60065 then you are of course at liberty to do so. IEC60065 has been written by people who understand audio/video products, the same may not apply to the people who wrote IEC60950. ------------------------------------------- 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [email protected] Dave Heald [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
