Here's a quote from a government study on the noise levels at the 2006 Stanley Cup Playoff's.
Noise Level at Hockey games
During game 3 of the series, the scoring of goals led to fairly obvious spikes in the noise level (Fig. 1). A level of 120 dB A is roughly equivalent to the sound level of a jet taking flight. (A-weighting is a filtering function applied to the noise dosimeter so that it is sensitive to input frequencies in the same way as the typical adult ear is.) The intermissions offered a temporary reprieve for the ears, but even during those interludes, the noise level was such that in an equivalent 8 h/day workplace environment, hearing protection would be required by law.
The average exposure levels for each game (> 3 hours) were 104.1, 100.7 and 103.1 dB. Standards have been defined for maximum allowable daily noise doses,2 and an average level of 85 dB A for 8 hours is generally considered the maximum allowable daily noise dose. Stated differently, this means that there is a risk of hearing damage if you experience that level of noise for more than 8 hours. For each 3 dB increase in average noise level, the time you can safely stay at a level is halved. Thus, at 88 dB, it would take only 4 hours to reach the maximum allowable daily noise dose, at 91 dB it would take only 2 hours, and so on. For the levels experienced in game 3 of the series, the time to reach the maximum allowable daily noise dose was less than 6 minutes. In terms of projected noise dose, each person in the arena not wearing hearing protection received about 8100% of their daily allowable noise dose. Given that most fans do not wear hearing protection during hockey games, thousands are at risk for hearing damage.
Next time, I am taking my hearing aids out and putting my ear plugs in!