The Dynamic radial load rating is defined by the radial load by which 90% of a test batch of identical bearings undergo one million revolutions before any material fatigue begins to appear. ISO281 characterises the dynamic load rating and rating life of rolling bearings and is a very useful document.
The L10 life is connected with the Dynamic radial load rating. This is calculating how many hours 90% of a bearing sample set will last given specific load and speed data. This assumes the bearing is operating in optimal conditions and doesn’t account for wear, improper lubrication, contamination and shaft misalignment.
Carter can provide much more accurate lifetime calculations considering additional factors such as lubrication contamination, tilting moments, shock loads, vibration.