Final answer:
A decibel level difference of about 3 dB signifies a doubling of loudness in terms of sound intensity.
Step-by-step explanation:
The difference in decibel (dB) levels representing a doubling of "loudness" is about 3 dB. This is because a sound that is twice as intense as another sound has a sound level approximately 3 dB higher. For instance, a sound measured at 56.0 dB is twice as intense as a sound measured at 53.0 dB, and a sound at 97.0 dB is half as intense as a 100 dB sound. This relationship holds true regardless of the actual intensities, as long as they differ by a factor of two.