If you've ever seen a Jewish man with strings hanging out of his clothing, this is probably what you were seeing. There is no particular religious significance to the tallit (shawl) itself, other than the fact that it holds the tzitzit (fringes) on its corners.
Sound pressure or acoustic pressure is the local pressure deviation from the ambient (average, or equilibrium) atmospheric pressure, caused by a sound wave. In air, sound pressure can be measured using a microphone, and in water with a hydrophone. The SI unit of sound pressure is the pascal (Pa).
The noise level measures an average of 99 dB. You are wearing ear protection with an SNR of 19. Thus, the acoustic pressure on your ears is on average 99 â 19 = 80 dB. The higher the SNR, the higher the level of noise attenuation provided by the hearing protection.