cerpico et al;
Back tracking and reading my input over again I find myself in a defensive position here. My point is and has always been GREEN means GO, RED means STOP/WARNING (or an indication why the machine stopped).
The company to which I am employed, design and build verious testing facilities. Not process equipment. These are usually small sized (up to 4000lbs) equipments most are simi-portable. Not paper mills, mill hammers, steel mills, or etc..
My point was and continues to be: Indication of operation should give the operator some since of the degree of safety.
That is to say if you use RED indicator lights to show that the machine and all it's sub-circuits are operating normal you are giving that operator a false warning indication. If you do this, I believe this is old school philosophy.
//It appears most (not all) everyone this thread agrees that RED is STOP/WARNING\OSHA has lists of colors to be used as levels of HAZARDS:
Green: Safe
Orange: WARNING
Red: DANGER
Blue: INFORMATIONAL
others:
I use GREEN as a Start button. Red as a STOP button. (normally neither are illuminated). There may be a "HEAT", "COOL", "HUMIDIFY" or more switch(es). Those functions when "ON" would be shown energized with a AMBER indicator. Amber because it can be seen and are not a hazard when functioning or not. They are just to let the operator know that they or working (fuctional/cycled) to the process. You could tell me to use green and I would.
Auto-Shut down; Here, I use RED again only as an indicator to the operator as to: "LOOK" the machine stopped (automatically) approach with caution, find out why. Call your supervisor. The machine can be stopped by "E" stop, temperature, pressure or other harmful limits to its self or to personnel.
In my instance when I say the machine is "OFF" it's off (no auto restart). Only the temperature displays and chart recorder is energized to show the operator where things are or were in the process when it went down.
Cerpico; You yourself elude to the premis Green is GO, RED is stop.
I am saying the samething!!
I guess it comes down to this. If the machine is operating as it is designed, is safe or not. I say yes! and there should be no RED indicator lights lit if all is operating normal. If I approched a machine and pressed the "START" button and the panel lit up RED! I'd run like hell to get out of there. Ya see..
In the "ole" days, (Hey I'm an old guy), I remember the large red bullet nosed indicator panel lights. But these were on open frame, uncaged, unshrouded systems. Workers had to approach these machines with fear in their hearts.
When you start your car there should be no red light showing on the dash, or you'll be calling AAA.
We as a "modern" industrialized nation of standards have come far and away from that. Just because a piece of equipment is "ON" does not mean it's unsafe, nor should we as engineers do what was done fifty years ago.
I see no flaw in this logic, as you seem to do. I do see lack in the communicaton of our thoughts. Maybe your not totally wrong and maybe Iam not totally right, but I think we can meet somewhere in between.
I hope this clears up any confusion from what I have posted in the past. This is my philosophy.
What is obvious here is that there is no real clear standard (now) that we ALL can follow except that we all must try to do the very best we can to address, protect and annunciate the safe operational status to those operators of our individual equipments.
Iam still worried about my coffee maker, is that really a warning light or not?
I wish you all well
pennpoint