RE: Colors of indicators
Hi Folks This has been a thorny problem for the last 20yrs to my personal knowledge! I first encountered it in the late 60's/early 70's with IEC 204 (the predecessor to EN60204) and with medical equipment for use by the UK National Health Service. Over that period, the recommended colours have always been stated in IEC73, which has now become IEC60073:1996 BASIC AND SAFETY PRINCIPLES FOR MAN-MACHINE INTERFACE, MARKING AND IDENTIFICATION) . Originally it dealt only with colours of lights and pushbuttons and used the traffic light approach, i.e. - Red = Danger and/or stop now! - Yellow = Caution, and/or things may be going out of spec. - Greeen = All normal or OK However, the latest version of 60073 has been expanded significantly to cover general rules for assigning particular meanings to certain visual, acoustic and tactile indications, and irt has the status of a basic safety publication in accordance with IEC Guide 104 - which is probabaly why it is not mentioned in EN60950/UL 1950 etc. Some sectors of business are very picky on colours - notably medical standards (e.g. IEC 60601) and process industries standards (e.g.EN60204 etc) - because errors in interpretation of warning and caution indicators can have catastrophic effects! Others - such as the IT industry in general - seem far less concerned and are prepared to accept any convenient colours for indicators However, if you follow IEC 60073 you should - to the best of my knowledge - have no trouble anywhere (unless something else is called up in contract!) Regards John Allen Product Safety Manager Racal Radio Ltd. -- From: Crane, Lauren[SMTP:lcr...@bev.etn.com] Reply To: Crane, Lauren Sent: 27 April 1999 18:27 To: 'Allan, James'; 'emc-pstc' Subject:RE: Colors of indicators It is not so much that red not be used, but that it not be used for safe, normal, expected conditions of the equipment. One example of this is a PREFERENCE stated in EN 60204-1 section 10.3.2. (It does allow deviations based on specific agreement with customers.) I think the underlying thought is that red lights tend to indicate dangerous conditions from which an operator should run away or seek help immediately. I think an old spin on red lights may be that red for power on, for example, means this thing is armed and ready to fire, so watch out. However, it is expected these days that idle equipment is not hazardous and will not start up or take actions unexpectedly. Now power on is a normal safe condition for equipment (or should be, at least) and so the 'proper' color for power on lights is green or white. Other benign equipment states, such as indicators for moving parts being in a normal, expected location, should be treated similarly. Red LED's appeared in products alot because they were originally the cheapest, most available color. I only have access to UL 1950, but its 1.7.8.2 seems nearly in line with EN 60204-1 in that it allows red indicators provided that it is clear that safety is not involved. Lauren Crane Eaton Corporation. -Original Message- From: Allan, James [SMTP:james_al...@milgo.com] Sent: Tuesday, April 27, 1999 8:27 AM To: 'emc-pstc' Subject: Colors of indicators Several years ago I remember that indicators could not be red in color. This requirement seems to have gone away per EN60950 1.7.8.2. Could the group provide me with a bit of history as to where the original requirement to be not red came from. Was it a part of the German GS mark requirements or did it have a wider application in Europe than just GS marking? No great acts hang in the shadow of the answer, just a bit of curiosity. Jim Allan Senior Compliance Engineer Milgo Solutions Inc. E-mail james_al...@milgo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Re: Colors of indicators
Hi Jim, The first time I came across this requirement was when carrying out GS approval on a PC. It came from the German ergonomic standard ZH1/618. Regards, Chris. Allan, James james_al...@milgo.com on 27/04/99 13:27:21 Please respond to Allan, James james_al...@milgo.com Sent by: Allan, James james_al...@milgo.com To: 'emc-pstc' emc-p...@majordomo.ieee.org cc:(Chris Allen/GB/3Com) Subject: Colors of indicators Several years ago I remember that indicators could not be red in color. This requirement seems to have gone away per EN60950 1.7.8.2. Could the group provide me with a bit of history as to where the original requirement to be not red came from. Was it a part of the German GS mark requirements or did it have a wider application in Europe than just GS marking? No great acts hang in the shadow of the answer, just a bit of curiosity. Jim Allan Senior Compliance Engineer Milgo Solutions Inc. E-mail james_al...@milgo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
RE: Colors of indicators
It is not so much that red not be used, but that it not be used for safe, normal, expected conditions of the equipment. One example of this is a PREFERENCE stated in EN 60204-1 section 10.3.2. (It does allow deviations based on specific agreement with customers.) I think the underlying thought is that red lights tend to indicate dangerous conditions from which an operator should run away or seek help immediately. I think an old spin on red lights may be that red for power on, for example, means this thing is armed and ready to fire, so watch out. However, it is expected these days that idle equipment is not hazardous and will not start up or take actions unexpectedly. Now power on is a normal safe condition for equipment (or should be, at least) and so the 'proper' color for power on lights is green or white. Other benign equipment states, such as indicators for moving parts being in a normal, expected location, should be treated similarly. Red LED's appeared in products alot because they were originally the cheapest, most available color. I only have access to UL 1950, but its 1.7.8.2 seems nearly in line with EN 60204-1 in that it allows red indicators provided that it is clear that safety is not involved. Lauren Crane Eaton Corporation. -Original Message- From: Allan, James [SMTP:james_al...@milgo.com] Sent: Tuesday, April 27, 1999 8:27 AM To: 'emc-pstc' Subject: Colors of indicators Several years ago I remember that indicators could not be red in color. This requirement seems to have gone away per EN60950 1.7.8.2. Could the group provide me with a bit of history as to where the original requirement to be not red came from. Was it a part of the German GS mark requirements or did it have a wider application in Europe than just GS marking? No great acts hang in the shadow of the answer, just a bit of curiosity. Jim Allan Senior Compliance Engineer Milgo Solutions Inc. E-mail james_al...@milgo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
Colors of indicators
Several years ago I remember that indicators could not be red in color. This requirement seems to have gone away per EN60950 1.7.8.2. Could the group provide me with a bit of history as to where the original requirement to be not red came from. Was it a part of the German GS mark requirements or did it have a wider application in Europe than just GS marking? No great acts hang in the shadow of the answer, just a bit of curiosity. Jim Allan Senior Compliance Engineer Milgo Solutions Inc. E-mail james_al...@milgo.com - This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: unsubscribe emc-pstc (without the quotes). For help, send mail to ed.pr...@cubic.com, jim_bac...@monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).