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. | 518s | 439s | 373s | 316s | 268s | 228s | 193s | 164s | 139s | 118s | 100s | 85s | 72s | 61s | 52s | 44s | 37s | 32s | 27s | 23s | 19s | 16s | 14s | 12s | 10s |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 202404 | LHZ-00 | AR | 611 | -169 | -169 | -168 | -167 | -164 | -162 | -158 | -156 | -153 | -152 | -154 | -156 | -157 | -149 | -146 | -146 | -144 | -141 | -138 | -132 | -124 | -118 | -112 | -112 | -109 |
| 202403 | LHZ-00 | AR | 744 | -169 | -170 | -168 | -167 | -165 | -162 | -159 | -158 | -155 | -155 | -156 | -158 | -157 | -150 | -148 | -147 | -145 | -143 | -139 | -132 | -124 | -118 | -115 | -114 | -114 |
| 202402 | LHZ-00 | AR | 692 | -169 | -169 | -168 | -166 | -164 | -162 | -159 | -157 | -155 | -155 | -156 | -158 | -157 | -150 | -147 | -146 | -144 | -141 | -138 | -131 | -123 | -116 | -112 | -109 | -110 |
| 202401 | LHZ-00 | AR | 700 | -168 | -168 | -168 | -166 | -165 | -162 | -160 | -158 | -155 | -155 | -157 | -158 | -158 | -150 | -148 | -147 | -145 | -143 | -139 | -132 | -125 | -119 | -114 | -115 | -114 |
| 202312 | LHZ-00 | AR | 736 | -168 | -169 | -168 | -167 | -165 | -162 | -159 | -157 | -155 | -154 | -155 | -157 | -157 | -151 | -148 | -147 | -146 | -143 | -139 | -133 | -126 | -120 | -116 | -111 | -107 |
| 202311 | LHZ-00 | AR | 701 | -169 | -169 | -168 | -166 | -164 | -161 | -157 | -156 | -153 | -153 | -153 | -155 | -156 | -150 | -147 | -146 | -145 | -142 | -139 | -134 | -127 | -119 | -112 | -110 | -106 |
| 202310 | LHZ-00 | AR | 630 | -170 | -169 | -167 | -166 | -164 | -161 | -158 | -155 | -153 | -153 | -153 | -154 | -155 | -149 | -146 | -145 | -144 | -141 | -136 | -131 | -124 | -116 | -111 | -109 | -105 |
| 202309 | LHZ-00 | AR | 720 | -169 | -169 | -168 | -166 | -163 | -160 | -157 | -155 | -152 | -151 | -152 | -154 | -154 | -149 | -146 | -145 | -144 | -141 | -137 | -132 | -125 | -119 | -110 | -105 | -104 |
| 202308 | LHZ-00 | AR | 616 | -169 | -169 | -168 | -166 | -165 | -162 | -159 | -157 | -155 | -154 | -154 | -156 | -156 | -150 | -147 | -147 | -145 | -142 | -138 | -132 | -123 | -115 | -111 | -107 | -107 |
| 202307 | LHZ-00 | AR | 697 | -169 | -169 | -167 | -165 | -164 | -161 | -158 | -155 | -152 | -152 | -153 | -155 | -155 | -150 | -147 | -147 | -145 | -142 | -137 | -133 | -125 | -117 | -112 | -108 | -107 |
| 202306 | LHZ-00 | AR | 696 | -168 | -168 | -167 | -166 | -164 | -162 | -159 | -157 | -155 | -154 | -155 | -156 | -156 | -150 | -147 | -147 | -145 | -143 | -139 | -133 | -125 | -118 | -111 | -106 | -106 |
| 202305 | LHZ-00 | AR | 731 | -167 | -167 | -165 | -164 | -161 | -158 | -155 | -153 | -151 | -149 | -151 | -153 | -153 | -147 | -144 | -144 | -142 | -140 | -136 | -130 | -122 | -114 | -109 | -108 | -107 |
| 202304 | LHZ-00 | AR | 629 | -169 | -170 | -169 | -168 | -167 | -164 | -161 | -159 | -156 | -155 | -157 | -159 | -158 | -152 | -149 | -148 | -146 | -144 | -140 | -134 | -126 | -118 | -111 | -109 | -110 |
| 202303 | LHZ-00 | AR | 714 | -168 | -168 | -168 | -167 | -166 | -164 | -160 | -158 | -155 | -154 | -156 | -159 | -158 | -151 | -149 | -148 | -146 | -143 | -139 | -135 | -127 | -120 | -114 | -111 | -109 |
| 202302 | LHZ-00 | AR | 451 | -170 | -169 | -168 | -167 | -165 | -162 | -159 | -158 | -155 | -155 | -156 | -158 | -157 | -150 | -148 | -147 | -145 | -142 | -138 | -132 | -124 | -118 | -114 | -114 | -114 |
| 202301 | LHZ-00 | AR | 739 | -167 | -167 | -167 | -165 | -164 | -161 | -158 | -157 | -154 | -154 | -157 | -158 | -158 | -150 | -148 | -147 | -145 | -142 | -138 | -132 | -124 | -118 | -113 | -112 | -112 |
| 202212 | LHZ-00 | AR | 736 | -167 | -168 | -167 | -165 | -164 | -161 | -159 | -157 | -154 | -155 | -156 | -158 | -158 | -151 | -149 | -149 | -146 | -143 | -140 | -134 | -126 | -118 | -114 | -114 | -114 |
| 202211 | LHZ-00 | AR | 716 | -169 | -169 | -168 | -167 | -165 | -163 | -159 | -158 | -155 | -155 | -157 | -159 | -158 | -151 | -148 | -148 | -146 | -143 | -140 | -134 | -126 | -117 | -113 | -112 | -112 |
| 202210 | LHZ-00 | AR | 741 | -169 | -169 | -168 | -167 | -164 | -161 | -158 | -156 | -154 | -153 | -154 | -156 | -156 | -150 | -147 | -147 | -145 | -143 | -139 | -132 | -122 | -114 | -110 | -109 | -109 |
| 202209 | LHZ-00 | AR | 715 | -168 | -167 | -166 | -165 | -163 | -159 | -157 | -154 | -152 | -151 | -152 | -154 | -154 | -149 | -147 | -146 | -144 | -141 | -138 | -131 | -123 | -115 | -111 | -108 | -105 |
| 202208 | LHZ-00 | AR | 1 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 | 999 |
| 202205 | LHZ-00 | AR | 213 | -184 | -182 | -180 | -178 | -174 | -167 | -163 | -159 | -155 | -153 | -153 | -154 | -153 | -146 | -143 | -143 | -142 | -139 | -135 | -128 | -119 | -111 | -108 | -107 | -107 |
| 202204 | LHZ-00 | AR | 357 | -185 | -184 | -182 | -178 | -175 | -170 | -165 | -161 | -157 | -155 | -156 | -156 | -155 | -147 | -144 | -143 | -141 | -138 | -135 | -130 | -121 | -114 | -110 | -110 | -108 |
| 202203 | LHZ-00 | AR | 740 | -185 | -184 | -183 | -180 | -176 | -171 | -166 | -162 | -157 | -156 | -155 | -157 | -156 | -148 | -146 | -145 | -143 | -140 | -136 | -130 | -122 | -115 | -110 | -107 | -106 |
| 202202 | LHZ-00 | AR | 672 | -185 | -184 | -182 | -180 | -176 | -171 | -166 | -161 | -156 | -155 | -156 | -157 | -157 | -149 | -146 | -146 | -143 | -140 | -137 | -131 | -122 | -116 | -112 | -111 | -111 |
| 202201 | LHZ-00 | AR | 742 | -185 | -184 | -181 | -179 | -176 | -170 | -165 | -162 | -157 | -156 | -157 | -158 | -156 | -149 | -146 | -146 | -144 | -141 | -137 | -133 | -126 | -118 | -113 | -112 | -111 |
| 202112 | LHZ-00 | AR | 743 | -180 | -179 | -177 | -173 | -170 | -166 | -161 | -156 | -150 | -149 | -151 | -154 | -154 | -146 | -143 | -144 | -143 | -141 | -139 | -136 | -129 | -122 | -118 | -116 | -113 |
| 202111 | LHZ-00 | AR | 720 | -138 | -139 | -139 | -139 | -138 | -138 | -138 | -138 | -138 | -140 | -141 | -141 | -139 | -139 | -141 | -143 | -142 | -141 | -139 | -136 | -132 | -123 | -118 | -114 | -112 |
| 202110 | LHZ-00 | AR | 744 | -136 | -136 | -136 | -136 | -136 | -136 | -135 | -135 | -134 | -136 | -138 | -138 | -137 | -136 | -138 | -141 | -140 | -139 | -137 | -134 | -127 | -121 | -117 | -113 | -111 |
| 202109 | LHZ-00 | AR | 718 | -133 | -133 | -133 | -133 | -133 | -132 | -132 | -132 | -132 | -133 | -135 | -136 | -135 | -135 | -137 | -139 | -140 | -138 | -136 | -131 | -123 | -116 | -112 | -111 | -110 |
| 202108 | LHZ-00 | AR | 193 | -166 | -167 | -165 | -164 | -163 | -160 | -159 | -154 | -151 | -151 | -151 | -154 | -155 | -148 | -146 | -145 | -143 | -141 | -137 | -131 | -124 | -116 | -112 | -109 | -102 |
| 202105 | LHZ-00 | AR | 289 | -168 | -167 | -165 | -164 | -163 | -160 | -158 | -156 | -153 | -153 | -154 | -157 | -156 | -148 | -146 | -146 | -144 | -142 | -138 | -130 | -121 | -113 | -111 | -108 | -105 |
| 202104 | LHZ-00 | AR | 720 | -169 | -168 | -167 | -166 | -164 | -161 | -158 | -157 | -154 | -154 | -155 | -158 | -158 | -150 | -147 | -147 | -145 | -142 | -138 | -131 | -124 | -117 | -113 | -113 | -112 |
| 202103 | LHZ-00 | AR | 744 | -170 | -169 | -168 | -167 | -166 | -163 | -160 | -159 | -155 | -156 | -157 | -159 | -159 | -151 | -148 | -147 | -146 | -143 | -139 | -133 | -125 | -118 | -113 | -110 | -110 |
| 202102 | LHZ-00 | AR | 653 | -170 | -169 | -168 | -167 | -166 | -163 | -160 | -159 | -156 | -156 | -158 | -160 | -160 | -152 | -149 | -149 | -146 | -143 | -139 | -133 | -124 | -117 | -114 | -113 | -113 |
| 202101 | LHZ-00 | AR | 744 | -169 | -168 | -166 | -165 | -163 | -160 | -157 | -157 | -154 | -155 | -157 | -159 | -158 | -150 | -148 | -148 | -145 | -142 | -138 | -131 | -123 | -118 | -116 | -116 | -116 |
| 202012 | LHZ-00 | AR | 744 | -169 | -168 | -167 | -166 | -165 | -161 | -159 | -157 | -155 | -155 | -157 | -159 | -159 | -151 | -148 | -148 | -146 | -143 | -140 | -134 | -127 | -121 | -116 | -115 | -111 |
| 202011 | LHZ-00 | AR | 720 | -170 | -170 | -168 | -168 | -166 | -164 | -161 | -159 | -157 | -157 | -159 | -161 | -160 | -152 | -149 | -148 | -146 | -144 | -140 | -135 | -128 | -121 | -117 | -114 | -113 |
| 202010 | LHZ-00 | AR | 744 | -169 | -168 | -167 | -166 | -164 | -162 | -159 | -156 | -153 | -153 | -154 | -156 | -157 | -150 | -147 | -146 | -145 | -142 | -138 | -134 | -126 | -117 | -113 | -112 | -106 |
| 202009 | LHZ-00 | AR | 720 | -169 | -167 | -167 | -165 | -163 | -160 | -157 | -155 | -152 | -151 | -153 | -156 | -156 | -150 | -146 | -146 | -145 | -142 | -138 | -132 | -124 | -118 | -115 | -111 | -106 |
| 202008 | LHZ-00 | AR | 744 | -169 | -167 | -166 | -165 | -163 | -161 | -157 | -155 | -153 | -153 | -154 | -156 | -156 | -151 | -148 | -147 | -145 | -143 | -139 | -133 | -126 | -119 | -111 | -109 | -106 |
| 202007 | LHZ-00 | AR | 744 | -169 | -168 | -167 | -166 | -164 | -161 | -159 | -156 | -154 | -154 | -154 | -157 | -157 | -151 | -148 | -147 | -145 | -143 | -138 | -133 | -126 | -118 | -112 | -108 | -107 |
| 202006 | LHZ-00 | AR | 719 | -168 | -168 | -166 | -165 | -164 | -161 | -158 | -156 | -153 | -153 | -154 | -156 | -157 | -149 | -146 | -145 | -144 | -141 | -137 | -130 | -122 | -114 | -110 | -107 | -106 |
| 202005 | LHZ-00 | AR | 736 | -169 | -168 | -166 | -165 | -163 | -160 | -157 | -155 | -152 | -152 | -153 | -156 | -157 | -150 | -147 | -147 | -145 | -142 | -138 | -131 | -123 | -116 | -110 | -108 | -108 |
| 202004 | LHZ-00 | AR | 714 | -170 | -169 | -168 | -167 | -166 | -163 | -160 | -158 | -155 | -155 | -157 | -159 | -159 | -151 | -148 | -148 | -146 | -143 | -140 | -133 | -124 | -117 | -113 | -111 | -112 |
| 202003 | LHZ-00 | AR | 743 | -168 | -168 | -167 | -166 | -164 | -161 | -158 | -157 | -153 | -153 | -155 | -158 | -158 | -150 | -147 | -147 | -146 | -143 | -139 | -134 | -125 | -118 | -114 | -111 | -110 |
| 202002 | LHZ-00 | AR | 693 | -170 | -169 | -168 | -167 | -165 | -162 | -160 | -158 | -156 | -156 | -157 | -159 | -159 | -151 | -149 | -147 | -146 | -143 | -139 | -135 | -127 | -119 | -114 | -113 | -111 |
| 202001 | LHZ-00 | AR | 737 | -169 | -167 | -166 | -165 | -164 | -161 | -158 | -157 | -154 | -155 | -156 | -159 | -159 | -151 | -148 | -147 | -146 | -143 | -138 | -133 | -125 | -119 | -115 | -113 | -112 |
| 201912 | LHZ-00 | AR | 744 | -170 | -169 | -167 | -165 | -165 | -161 | -159 | -157 | -154 | -155 | -157 | -159 | -159 | -151 | -149 | -149 | -147 | -144 | -140 | -135 | -127 | -122 | -117 | -114 | -112 |
| 201911 | LHZ-00 | AR | 720 | -171 | -170 | -168 | -167 | -166 | -163 | -160 | -159 | -156 | -157 | -158 | -160 | -160 | -152 | -149 | -148 | -147 | -144 | -140 | -135 | -126 | -118 | -115 | -114 | -113 |
| 201910 | LHZ-00 | AR | 737 | -170 | -169 | -168 | -166 | -165 | -161 | -159 | -158 | -156 | -155 | -156 | -159 | -159 | -151 | -149 | -148 | -146 | -144 | -139 | -133 | -125 | -118 | -113 | -111 | -111 |
| 201909 | LHZ-00 | AR | 720 | -169 | -168 | -167 | -165 | -163 | -161 | -157 | -156 | -153 | -153 | -153 | -155 | -156 | -150 | -147 | -147 | -145 | -142 | -137 | -131 | -123 | -115 | -111 | -109 | -108 |
| 201908 | LHZ-00 | AR | 744 | -168 | -167 | -167 | -165 | -163 | -161 | -158 | -155 | -153 | -152 | -153 | -156 | -156 | -150 | -147 | -146 | -145 | -142 | -138 | -132 | -125 | -117 | -112 | -109 | -107 |
| 201907 | LHZ-00 | AR | 743 | -167 | -166 | -164 | -163 | -161 | -159 | -156 | -153 | -151 | -151 | -151 | -154 | -155 | -148 | -146 | -145 | -143 | -141 | -137 | -130 | -121 | -114 | -110 | -107 | -106 |
| 201906 | LHZ-00 | AR | 720 | -165 | -164 | -163 | -162 | -160 | -157 | -154 | -153 | -151 | -152 | -154 | -157 | -158 | -152 | -149 | -148 | -147 | -145 | -141 | -135 | -126 | -119 | -115 | -113 | -109 |
| 201905 | LHZ-00 | AR | 654 | -152 | -152 | -152 | -152 | -152 | -151 | -150 | -150 | -150 | -151 | -153 | -156 | -157 | -150 | -148 | -148 | -146 | -143 | -139 | -132 | -124 | -117 | -113 | -110 | -108 |
| 201903 | LHZ-00 | AR | 539 | -168 | -168 | -168 | -167 | -165 | -162 | -159 | -158 | -156 | -155 | -156 | -158 | -158 | -151 | -149 | -148 | -146 | -144 | -139 | -133 | -124 | -118 | -114 | -111 | -108 |
| 201902 | LHZ-00 | AR | 103 | -161 | -163 | -162 | -159 | -159 | -157 | -154 | -151 | -149 | -149 | -152 | -154 | -155 | -149 | -147 | -147 | -145 | -142 | -138 | -134 | -125 | -117 | -111 | -108 | -110 |
| 201812 | LHZ-00 | AR | 495 | -167 | -167 | -166 | -166 | -165 | -161 | -159 | -158 | -155 | -155 | -157 | -159 | -158 | -150 | -148 | -148 | -146 | -143 | -139 | -133 | -126 | -119 | -115 | -112 | -111 |
| 201811 | LHZ-00 | AR | 719 | -168 | -169 | -167 | -167 | -166 | -162 | -159 | -158 | -156 | -156 | -157 | -159 | -158 | -151 | -148 | -148 | -146 | -143 | -140 | -134 | -127 | -119 | -114 | -111 | -109 |
| 201810 | LHZ-00 | AR | 743 | -167 | -168 | -167 | -166 | -163 | -160 | -158 | -156 | -153 | -153 | -155 | -157 | -157 | -149 | -147 | -146 | -145 | -142 | -139 | -133 | -124 | -116 | -110 | -108 | -109 |
| 201809 | LHZ-00 | AR | 697 | -166 | -167 | -165 | -164 | -162 | -159 | -155 | -153 | -151 | -150 | -152 | -154 | -154 | -148 | -146 | -145 | -143 | -141 | -137 | -130 | -122 | -114 | -112 | -106 | -104 |
| 201808 | LHZ-00 | AR | 743 | -168 | -168 | -167 | -166 | -165 | -162 | -159 | -157 | -154 | -154 | -155 | -158 | -157 | -150 | -147 | -147 | -145 | -142 | -138 | -132 | -123 | -116 | -113 | -112 | -110 |
| 201807 | LHZ-00 | AR | 288 | -168 | -168 | -167 | -167 | -165 | -163 | -159 | -157 | -154 | -153 | -154 | -157 | -157 | -149 | -147 | -147 | -145 | -142 | -137 | -130 | -122 | -118 | -114 | -109 | -106 |
| 201806 | LHZ-00 | AR | 512 | -168 | -168 | -167 | -167 | -165 | -162 | -159 | -157 | -153 | -153 | -154 | -157 | -156 | -149 | -146 | -147 | -145 | -142 | -138 | -130 | -123 | -116 | -113 | -108 | -108 |
| 201805 | LHZ-00 | AR | 744 | -166 | -166 | -165 | -164 | -163 | -160 | -157 | -154 | -151 | -151 | -152 | -156 | -155 | -149 | -146 | -146 | -144 | -142 | -138 | -132 | -125 | -116 | -111 | -111 | -112 |
| 201804 | LHZ-00 | AR | 720 | -167 | -167 | -167 | -166 | -165 | -162 | -159 | -158 | -155 | -154 | -156 | -159 | -158 | -150 | -147 | -147 | -145 | -142 | -138 | -133 | -125 | -117 | -113 | -112 | -111 |
| 201803 | LHZ-00 | AR | 744 | -167 | -168 | -168 | -166 | -165 | -162 | -160 | -157 | -154 | -154 | -156 | -158 | -158 | -150 | -147 | -147 | -145 | -143 | -139 | -135 | -128 | -119 | -114 | -111 | -110 |
| 201802 | LHZ-00 | AR | 669 | -166 | -166 | -166 | -165 | -164 | -161 | -159 | -158 | -155 | -155 | -157 | -159 | -158 | -150 | -148 | -147 | -145 | -143 | -139 | -135 | -127 | -119 | -114 | -114 | -114 |
| 201801 | LHZ-00 | AR | 738 | -168 | -169 | -167 | -166 | -165 | -163 | -160 | -159 | -156 | -156 | -157 | -160 | -160 | -152 | -149 | -149 | -147 | -144 | -140 | -135 | -127 | -119 | -115 | -115 | -113 |