I think you are talking about the CEA-2006 Power Ratings. Here is the write-up on it.
From Alpine.
Alpine Leadership
Alpine is pleased to be one of the first manufacturers to adopt the new Consumer Electronics Association certification program measuring amplifier performance. The new standard is designated as CEA-2006 - Testing and Measurement Methods for Mobile Audio Amplifiers, including built-in Amplifiers in Head Units.
How It Benefits You
CEA-2006 is the new industry standard and was designed with you, the consumer in mind. By using the CEA-2006 power amplifier rating, you will be able to easily and accurately compare the performance of amplifiers and receivers(head units). Currently, there is a lot of confusion on exactly how much power an amp actually puts out because manufacturers are using different rating systems. Beginning in 2004, all Alpine products stamped with the CEA-2006 logo carry the assurance the power rating and specs related with the amplifier are true and accurate and the product conforms to the standard.
How it Works
The primary measurement methods outlined in CEA-2006 provide power output levels, the signal-to-noise ratio and total harmonic distortion plus noise (THD+N). With the new standard, you should expect to see two primary ratings - an amplifier's primary power output in watts (RMS) and the signal-to-noise ratio in dBA. Using 14.4 volts, the primary power output in watts is measured at a level with less than 1 percent (THD+N) to indicate how much continuous power the amplifier delivers at that low distortion level. The signal-to-noise ratio is measured at a reference level of 1 watt. A larger signal-to-noise ratio number indicates more desirable audio and less noise in an amplifier's output.