Checking standards

In the past I was on a project which used a color-coded checking procedure. I thought this was an industry standard but I have not been able to find a description of this procedure in an online search (using both color and colour as search words.)

Yellow was for items which were verified and ok. Green was for items to be deleted.
Red was for changes,corrections and additions. Blue was for checker notes (such as calculations) and not to be added to the corrected drawing.

Is this a standardized procedure? If so, is the a place on line which has a description of it?

Dan Rosenberger
<a href="/group/PipingDesign/post?postID=E53_Qgnwf_fxcgabzTEPQnl_98zqp1xu2lKqgj9AhItcilvIgntpZmyq_CdwuEmPi8FncnFfaq0uYdOj8CqtdFuk">drosenberger@frankirish.com</a> Received on Mon Mar 28 11:09:00 2005