"R" in the numeric designation signifies that the 1998 standard was reaffirmed (recertified) as an American National Standard in 2007 & 2015. No changes can be made to a standard during reaffirmation.
The standard provides functional, performance and design requirements for lubricating oil systems for diesel generators that provide emergency on-site power for light water reactor nuclear power plants. The standard addresses all mechanical equipment associated with the lubricating oil system with the exception of engine-mounted components. These components, which are mounted directly to engine structure itself, are excluded, except to define interface requirements. This standard also includes the lubricating oil system instrumentation and control functional requirements. It excludes motors, motor control centers, switchgear, cables, and other electrical equipment used in the operation of the lubricating oil system, except to define interface requirements.