[DB]

From the box of inexpensive foam earplugs I have:

Attenuation vs. Frequency
36.3 dB @ 125 Hz
38.5 dB @ 250 Hz
41.5 dB @ 500 Hz
39.4 dB @ 1.0 kHz
39.7 dB @ 2.0 kHz
46.3 dB @ 4.0 kHz
46.4 dB @ 8.0 kHz

These are nothing special earplugs. Professional earplugs are better. Damage to one's hearing is function of both sound pressure and time. Rock concerts are commonly in the 110 to 120+ dB sound pressure range near the stage. At those sound pressure levels it takes accumulated time to do permanent damage (10 minutes is unlikely to cause permanent damage). Long periods can easily cause damage at these levels.

The 150 dB sound pressure reported in this article is likely at or near the source. With 40 dB of attenuation from the earplugs the sound pressures would be around 110 dB even close to the source. No hearing damage will occur unless it is present for a long period of time. In addition it would only be real annoying, but not loud enough to drive you back.

The sound level drops 6 dB every time you double the distance from the source in open space. If the sound pressure is 150 dB 1 meter from the source, it would drop to 120 dB at 32 meters (about 106 feet) away. With earplugs it would be quieter than the typical smoke detector.

Typical home speakers produce about 96 dB sound pressure levels at 1 watt input power at 1 meter. A 100 watt amplifier could drive those speakers to 116 dB sound pressure levels before clipping (per channel).

[Gondring]

And earplugs covered by earmuffs... even more protection.

[wideminded]

46.4 dB @ 8.0 kHz

For some reason most hearing tests cut off at 8 KHz. I know someone who passed a hearing test and yet when I tested her hearing with higher frequencies, she couldn't hear anything above 9 KHz. It seems to me that the standard hearing test is probably not finding a lot of people who already have some hearing damage.