• Quiet Noise Pollution Index(NPI):
    0-4 (Daytime,7AM-8PM)
    0-3 (Nighttime,8PM-7AM)
  • Moderate Noise Pollution Index(NPI):
    4-8 (Daytime,7AM-8PM)
    3-7 (Nighttime,8PM-7AM)
  • Noisy Noise Pollution Index(NPI):
    >8 (Daytime,7AM-8PM)
    >7 (Nighttime,8PM-7AM)