The audience sound level exposure should be limited to an Event LAeq of no more than 107 dB or C-weighted peak sound pressure levels of no more than 140 dB.
Where practical, the audience should not be allowed within 3m of any loudspeaker. This can be achieved by the use of approved safety barriers and dedicated stewards, wearing appropriate hearing protection.
Noise nuisance to neighbours is considered in the Pollution Control Section.
For full and comprehensive guidance: Health and Safety Executive