WHO recommendation cut off for noise in industrial city:

WHO Guidelines for Noise Exposure Specific Environment Critical Health Effects LA eq Time base LA Max fast 1) Outdoor Living area Serious annoyance daytime and evening.Moderate annoyance daytime & evening. 55 50 16 16 - - 2) Dwelling, Indoors Inside bed rooms Speech intelligibility & moderate annoyance.Sleep disturbance, night time. 35 30 16 8 45 3) Outside bedrooms Sleep disturbance, window open. 45 8 60 4) School classroom Speech intelligibility disturbance of information extraction, message communication. 30 During class - 5) School playground Annoyance 55 During play - 6) Hospital wards, rooms indoors Sleep disturbance night time. Sleep disturbance day time. 30 30 16 8 40 - 7) Industrial, commercial, shopping & traffic areas Hearing impairment 70 24 110 8) Ceremonies festivals events Hearing impairment 100 4 110 9) Headphones Hearing impairment (free - field values) 85 1 110