Noise Levels at Different Periods
The table below gives the decibel 10% noise level (in db) for each month in
several period bands. The 10% noise level is defined as the signal
level not exceeded 10% of the time, based on hourly measurements. Each entry in the
table is color coded with reference to the New Low Noise Model (NLNM, Peterson, 1993):
navy, -6 db < value-NLNM < -3 db
blue, -3 db < value-NLNM < 3 db
aqua, 3 db < value-NLNM < 6 db
lime, 6 db < value-NLNM < 9 db
yellow, 9 db < value-NLNM < 12 db
orange, 12 db < value-NLNM < 15 db
red, 15 db < value-NLNM < 20 db
fuchsia, 20 db < value-NLNM < 25 db
silver, value-NLNM < -6 db, value-NLNM > 25 db
Black indicates that there was an insufficient number of hourly measurements to calculate a noise level.
| Month | Chan. | Qual. | # obs. | 268s | 228s | 193s | 164s | 139s | 118s | 100s | 85s | 72s | 61s | 52s | 44s | 37s | 32s | 27s | 23s | 19s | 16s | 14s | 12s | 10s |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 201204 | LHZ | AR | 24 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 |
| 201203 | LHZ | AR | 672 | -179 | -180 | -181 | -181 | -181 | -180 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -173 | -164 | -156 | -153 | -153 | -149 |
| 201202 | LHZ | AR | 359 | -179 | -180 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -176 | -170 | -161 | -153 | -152 | -151 | -142 |
| 201201 | LHZ | AR | 744 | -180 | -181 | -181 | -181 | -181 | -180 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -171 | -162 | -155 | -153 | -151 | -146 |
| 201112 | LHZ | AR | 735 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -171 | -163 | -155 | -152 | -152 | -146 |
| 201111 | LHZ | AR | 720 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -173 | -164 | -156 | -152 | -151 | -148 |
| 201110 | LHZ | AR | 744 | -177 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -171 | -163 | -156 | -155 | -154 | -152 |
| 201109 | LHZ | AR | 706 | -176 | -177 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -177 | -173 | -163 | -158 | -156 | -154 | -152 |
| 201108 | LHZ | AR | 744 | -175 | -177 | -178 | -178 | -179 | -179 | -180 | -180 | -181 | -181 | -181 | -180 | -180 | -179 | -176 | -172 | -164 | -157 | -157 | -160 | -154 |
| 201107 | LHZ | AR | 744 | -176 | -177 | -178 | -179 | -179 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -177 | -173 | -165 | -159 | -158 | -160 | -155 |
| 201106 | LHZ | AR | 720 | -176 | -177 | -179 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -179 | -176 | -173 | -164 | -157 | -157 | -160 | -153 |
| 201105 | LHZ | AR | 744 | -178 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -182 | -181 | -181 | -180 | -176 | -171 | -164 | -158 | -157 | -156 | -154 |
| 201104 | LHZ | AR | 720 | -178 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -179 | -176 | -171 | -162 | -155 | -156 | -156 | -151 |
| 201103 | LHZ | AR | 744 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -179 | -175 | -170 | -162 | -155 | -153 | -152 | -151 |
| 201102 | LHZ | AR | 660 | -180 | -181 | -181 | -182 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -181 | -181 | -179 | -176 | -171 | -162 | -154 | -152 | -152 | -149 |
| 201101 | LHZ | AR | 742 | -180 | -181 | -182 | -181 | -181 | -180 | -181 | -181 | -182 | -182 | -182 | -181 | -180 | -179 | -176 | -169 | -160 | -153 | -150 | -150 | -144 |
| 201012 | LHZ | AR | 744 | -181 | -182 | -182 | -182 | -182 | -182 | -182 | -182 | -183 | -183 | -183 | -182 | -181 | -180 | -178 | -174 | -165 | -157 | -152 | -152 | -151 |
| 201011 | LHZ | AR | 718 | -179 | -181 | -181 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -179 | -177 | -172 | -164 | -156 | -151 | -150 | -151 |
| 201010 | LHZ | AR | 689 | -177 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -177 | -173 | -164 | -156 | -154 | -153 | -150 |
| 201009 | LHZ | AR | 667 | -176 | -178 | -179 | -180 | -180 | -181 | -181 | -181 | -182 | -182 | -182 | -181 | -180 | -179 | -177 | -172 | -163 | -157 | -156 | -158 | -156 |
| 201008 | LHZ | AR | 744 | -175 | -177 | -178 | -179 | -179 | -180 | -180 | -181 | -181 | -182 | -181 | -181 | -180 | -179 | -177 | -172 | -163 | -157 | -158 | -161 | -153 |
| 201007 | LHZ | AR | 744 | -175 | -177 | -178 | -179 | -179 | -179 | -180 | -180 | -181 | -181 | -181 | -180 | -179 | -178 | -176 | -173 | -164 | -157 | -158 | -160 | -154 |
| 201006 | LHZ | AR | 720 | -176 | -177 | -179 | -179 | -179 | -180 | -180 | -181 | -181 | -182 | -181 | -181 | -180 | -179 | -176 | -172 | -163 | -157 | -158 | -160 | -154 |
| 201005 | LHZ | AR | 743 | -177 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -172 | -163 | -157 | -158 | -160 | -152 |
| 201004 | LHZ | AR | 665 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -182 | -181 | -181 | -181 | -179 | -177 | -172 | -163 | -155 | -153 | -153 | -147 |
| 201003 | LHZ | AR | 512 | -179 | -180 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -182 | -181 | -181 | -180 | -179 | -175 | -170 | -161 | -153 | -151 | -151 | -143 |
| 201002 | LHZ | AR | 557 | -180 | -181 | -182 | -182 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -171 | -163 | -156 | -152 | -152 | -149 |
| 201001 | LHZ | AR | 683 | -180 | -181 | -181 | -181 | -181 | -180 | -181 | -181 | -182 | -182 | -182 | -181 | -181 | -179 | -176 | -170 | -161 | -153 | -149 | -149 | -146 |
| 200912 | LHZ | AR | 689 | -180 | -181 | -181 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -171 | -162 | -154 | -151 | -149 | -147 |
| 200911 | LHZ | AR | 719 | -178 | -179 | -180 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -178 | -173 | -164 | -156 | -152 | -151 | -148 |
| 200910 | LHZ | AR | 744 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -176 | -170 | -162 | -156 | -155 | -155 | -151 |
| 200909 | LHZ | AR | 720 | -175 | -176 | -178 | -178 | -179 | -179 | -180 | -181 | -181 | -181 | -181 | -180 | -180 | -179 | -177 | -173 | -165 | -159 | -158 | -157 | -154 |
| 200908 | LHZ | AR | 744 | -174 | -175 | -177 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -176 | -173 | -165 | -158 | -158 | -161 | -157 |
| 200907 | LHZ | AR | 739 | -174 | -175 | -177 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -180 | -179 | -179 | -178 | -176 | -173 | -166 | -159 | -157 | -161 | -158 |
| 200906 | LHZ | AR | 671 | -175 | -177 | -178 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -179 | -177 | -173 | -165 | -157 | -157 | -161 | -155 |
| 200905 | LHZ | AR | 719 | -175 | -176 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -176 | -173 | -165 | -158 | -159 | -161 | -157 |
| 200904 | LHZ | AR | 695 | -176 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -177 | -173 | -164 | -157 | -157 | -159 | -153 |
| 200903 | LHZ | AR | 730 | -177 | -178 | -180 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -173 | -164 | -156 | -154 | -154 | -152 |
| 200902 | LHZ | AR | 671 | -178 | -180 | -181 | -182 | -181 | -181 | -181 | -182 | -182 | -183 | -182 | -182 | -181 | -180 | -177 | -172 | -162 | -155 | -153 | -153 | -147 |
| 200901 | LHZ | AR | 743 | -178 | -180 | -180 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -181 | -179 | -176 | -172 | -164 | -157 | -153 | -152 | -150 |
| 200812 | LHZ | AR | 744 | -178 | -179 | -180 | -180 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -172 | -163 | -155 | -154 | -153 | -151 |
| 200811 | LHZ | AR | 719 | -175 | -177 | -178 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -179 | -177 | -174 | -165 | -158 | -154 | -153 | -151 |
| 200810 | LHZ | AR | 744 | -174 | -176 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -180 | -179 | -178 | -176 | -171 | -163 | -156 | -154 | -153 | -151 |
| 200809 | LHZ | AR | 695 | -173 | -175 | -176 | -177 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -179 | -178 | -178 | -176 | -172 | -164 | -157 | -157 | -157 | -153 |
| 200808 | LHZ | AR | 331 | -172 | -173 | -175 | -176 | -177 | -178 | -178 | -179 | -178 | -179 | -178 | -178 | -177 | -176 | -175 | -172 | -164 | -159 | -158 | -158 | -155 |
| 200807 | LHZ | AR | 171 | -173 | -174 | -175 | -176 | -178 | -178 | -178 | -179 | -179 | -179 | -179 | -178 | -177 | -177 | -175 | -171 | -162 | -157 | -157 | -158 | -152 |
| 200806 | LHZ | AR | 694 | -174 | -175 | -176 | -178 | -178 | -179 | -179 | -179 | -180 | -180 | -179 | -179 | -178 | -178 | -176 | -171 | -162 | -156 | -157 | -161 | -155 |
| 200805 | LHZ | AR | 719 | -174 | -176 | -177 | -178 | -179 | -179 | -179 | -180 | -181 | -180 | -180 | -180 | -179 | -179 | -176 | -173 | -165 | -158 | -157 | -159 | -155 |
| 200804 | LHZ | AR | 710 | -175 | -176 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -180 | -180 | -179 | -176 | -173 | -164 | -157 | -155 | -156 | -153 |
| 200803 | LHZ | AR | 720 | -175 | -177 | -178 | -178 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -176 | -171 | -162 | -155 | -154 | -154 | -149 |
| 200802 | LHZ | AR | 538 | -176 | -177 | -178 | -179 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -179 | -176 | -170 | -160 | -153 | -151 | -151 | -142 |
| 200801 | LHZ | AR | 737 | -176 | -177 | -178 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -180 | -180 | -179 | -176 | -171 | -161 | -154 | -152 | -152 | -145 |
| 200712 | LHZ | AR | 727 | -174 | -176 | -177 | -178 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -176 | -171 | -162 | -154 | -151 | -151 | -145 |
| 200711 | LHZ | AR | 658 | -175 | -176 | -178 | -178 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -175 | -172 | -165 | -156 | -153 | -152 | -152 |
| 200710 | LHZ | AR | 725 | -176 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -182 | -181 | -181 | -180 | -179 | -177 | -173 | -165 | -157 | -153 | -153 | -152 |
| 200709 | LHZ | AR | 627 | -175 | -176 | -178 | -178 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -180 | -179 | -176 | -171 | -163 | -157 | -157 | -158 | -152 |
| 200708 | LHZ | AR | 728 | -174 | -176 | -177 | -178 | -179 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -176 | -172 | -164 | -158 | -159 | -161 | -157 |
| 200707 | LHZ | AR | 735 | -175 | -176 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -181 | -180 | -180 | -179 | -178 | -176 | -173 | -166 | -160 | -160 | -162 | -158 |
| 200706 | LHZ | AR | 469 | -175 | -176 | -178 | -178 | -179 | -179 | -180 | -180 | -181 | -181 | -180 | -180 | -179 | -179 | -176 | -174 | -165 | -158 | -159 | -163 | -157 |
| 200705 | LHZ | AR | 740 | -176 | -178 | -179 | -179 | -180 | -180 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -179 | -177 | -173 | -163 | -157 | -158 | -160 | -154 |
| 200704 | LHZ | AR | 663 | -177 | -178 | -179 | -179 | -179 | -179 | -180 | -180 | -181 | -181 | -180 | -180 | -180 | -179 | -175 | -171 | -162 | -154 | -153 | -152 | -148 |
| 200703 | LHZ | AR | 674 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -181 | -182 | -182 | -182 | -181 | -181 | -180 | -177 | -171 | -161 | -154 | -153 | -154 | -151 |
| 200702 | LHZ | AR | 665 | -179 | -180 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -182 | -181 | -180 | -176 | -171 | -162 | -154 | -152 | -153 | -148 |
| 200701 | LHZ | AR | 737 | -179 | -180 | -181 | -181 | -181 | -180 | -181 | -181 | -182 | -182 | -182 | -181 | -181 | -179 | -176 | -171 | -161 | -153 | -151 | -151 | -146 |
| 200612 | LHZ | AR | 739 | -178 | -180 | -180 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -179 | -177 | -171 | -162 | -153 | -150 | -150 | -148 |
| 200611 | LHZ | AR | 719 | -177 | -179 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -182 | -182 | -181 | -181 | -180 | -177 | -173 | -164 | -156 | -154 | -154 | -151 |
| 200610 | LHZ | AR | 744 | -176 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -180 | -180 | -177 | -172 | -164 | -158 | -156 | -156 | -153 |
| 200609 | LHZ | AR | 712 | -173 | -176 | -177 | -178 | -179 | -178 | -179 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -176 | -171 | -162 | -157 | -157 | -158 | -152 |
| 200608 | LHZ | AR | 744 | -174 | -176 | -177 | -178 | -179 | -179 | -180 | -180 | -180 | -180 | -180 | -180 | -179 | -178 | -177 | -173 | -165 | -159 | -159 | -162 | -155 |
| 200607 | LHZ | AR | 744 | -173 | -175 | -176 | -177 | -178 | -178 | -179 | -179 | -179 | -180 | -179 | -179 | -178 | -177 | -175 | -171 | -163 | -157 | -158 | -160 | -154 |
| 200606 | LHZ | AR | 693 | -174 | -176 | -177 | -178 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -180 | -179 | -179 | -176 | -170 | -162 | -157 | -158 | -160 | -149 |
| 200605 | LHZ | AR | 744 | -175 | -176 | -178 | -179 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -180 | -180 | -179 | -176 | -172 | -163 | -157 | -156 | -157 | -152 |
| 200604 | LHZ | AR | 670 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -181 | -180 | -180 | -177 | -172 | -164 | -157 | -156 | -155 | -152 |
| 200603 | LHZ | AR | 744 | -178 | -179 | -180 | -181 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -181 | -181 | -180 | -177 | -173 | -164 | -155 | -153 | -153 | -150 |
| 200602 | LHZ | AR | 672 | -178 | -179 | -180 | -181 | -181 | -181 | -181 | -182 | -182 | -182 | -182 | -182 | -181 | -180 | -176 | -171 | -162 | -154 | -153 | -154 | -150 |
| 200601 | LHZ | AR | 742 | -178 | -179 | -180 | -180 | -181 | -180 | -180 | -181 | -181 | -181 | -181 | -181 | -180 | -179 | -176 | -171 | -161 | -153 | -151 | -151 | -143 |