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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 202012 | LHZ | AR | 122 | -173 | -175 | -176 | -178 | -180 | -178 | -179 | -180 | -180 | -180 | -180 | -182 | -182 | -183 | -182 | -181 | -180 | -177 | -173 | -168 | -160 | -152 | -148 | -146 | -140 |
| 202011 | LHZ | AR | 606 | -171 | -173 | -175 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -183 | -182 | -182 | -181 | -178 | -175 | -171 | -163 | -157 | -153 | -152 | -150 |
| 202010 | LHZ | AR | 693 | -171 | -172 | -174 | -176 | -178 | -179 | -180 | -181 | -182 | -181 | -182 | -183 | -184 | -184 | -183 | -183 | -181 | -179 | -176 | -173 | -167 | -161 | -158 | -154 | -152 |
| 202009 | LHZ | AR | 710 | -170 | -172 | -173 | -176 | -177 | -179 | -180 | -180 | -180 | -181 | -182 | -182 | -183 | -183 | -183 | -182 | -181 | -180 | -176 | -172 | -164 | -160 | -159 | -156 | -153 |
| 202008 | LHZ | AR | 732 | -168 | -170 | -172 | -174 | -175 | -177 | -179 | -180 | -180 | -181 | -182 | -183 | -183 | -184 | -184 | -183 | -182 | -180 | -178 | -175 | -167 | -162 | -161 | -160 | -156 |
| 202007 | LHZ | AR | 739 | -167 | -168 | -171 | -173 | -175 | -176 | -178 | -179 | -179 | -180 | -181 | -182 | -182 | -183 | -183 | -182 | -181 | -180 | -176 | -172 | -165 | -161 | -163 | -162 | -158 |
| 202006 | LHZ | AR | 714 | -167 | -170 | -172 | -174 | -176 | -177 | -178 | -179 | -180 | -180 | -181 | -182 | -183 | -183 | -183 | -183 | -182 | -180 | -177 | -173 | -165 | -159 | -160 | -161 | -156 |
| 202005 | LHZ | AR | 742 | -167 | -170 | -172 | -174 | -175 | -177 | -177 | -178 | -179 | -180 | -180 | -181 | -182 | -183 | -183 | -182 | -181 | -180 | -177 | -173 | -165 | -160 | -159 | -158 | -153 |
| 202004 | LHZ | AR | 715 | -170 | -172 | -175 | -176 | -178 | -178 | -179 | -180 | -180 | -181 | -181 | -182 | -183 | -183 | -183 | -183 | -182 | -180 | -176 | -172 | -164 | -159 | -156 | -154 | -152 |
| 202003 | LHZ | AR | 742 | -171 | -173 | -174 | -176 | -177 | -178 | -180 | -180 | -180 | -181 | -181 | -182 | -183 | -183 | -182 | -182 | -180 | -179 | -175 | -171 | -163 | -158 | -156 | -154 | -152 |
| 202002 | LHZ | AR | 618 | -172 | -174 | -175 | -177 | -178 | -180 | -180 | -181 | -181 | -181 | -181 | -182 | -182 | -183 | -182 | -182 | -180 | -178 | -175 | -170 | -162 | -155 | -151 | -151 | -149 |
| 202001 | LHZ | AR | 215 | -172 | -173 | -175 | -176 | -178 | -180 | -180 | -180 | -181 | -181 | -181 | -181 | -182 | -183 | -182 | -182 | -180 | -178 | -174 | -169 | -161 | -155 | -152 | -151 | -147 |
| 201912 | LHZ | AR | 212 | -174 | -175 | -175 | -177 | -179 | -180 | -180 | -180 | -181 | -181 | -182 | -182 | -183 | -183 | -183 | -182 | -180 | -178 | -176 | -172 | -164 | -157 | -153 | -152 | -150 |
| 201911 | LHZ | AR | 719 | -172 | -173 | -175 | -176 | -177 | -179 | -179 | -180 | -180 | -181 | -181 | -182 | -182 | -183 | -182 | -182 | -180 | -178 | -175 | -172 | -164 | -157 | -153 | -152 | -151 |
| 201910 | LHZ | AR | 741 | -168 | -170 | -172 | -174 | -176 | -177 | -179 | -180 | -180 | -181 | -182 | -182 | -183 | -183 | -183 | -182 | -181 | -179 | -176 | -171 | -162 | -156 | -152 | -151 | -150 |
| 201909 | LHZ | AR | 709 | -168 | -170 | -173 | -175 | -177 | -178 | -179 | -180 | -181 | -181 | -182 | -182 | -183 | -183 | -183 | -182 | -181 | -180 | -177 | -171 | -163 | -159 | -158 | -156 | -152 |
| 201908 | LHZ | AR | 700 | -165 | -167 | -170 | -172 | -174 | -175 | -177 | -178 | -179 | -180 | -181 | -181 | -182 | -183 | -183 | -182 | -181 | -180 | -176 | -173 | -165 | -160 | -160 | -159 | -155 |
| 201907 | LHZ | AR | 578 | -166 | -168 | -170 | -172 | -174 | -176 | -177 | -178 | -179 | -179 | -180 | -181 | -182 | -182 | -182 | -181 | -180 | -179 | -176 | -172 | -163 | -159 | -161 | -162 | -155 |
| 201906 | LHZ | AR | 712 | -166 | -170 | -171 | -172 | -174 | -176 | -177 | -178 | -179 | -179 | -180 | -181 | -182 | -182 | -182 | -182 | -181 | -180 | -177 | -173 | -165 | -160 | -161 | -161 | -156 |
| 201905 | LHZ | AR | 742 | -167 | -169 | -171 | -173 | -175 | -176 | -178 | -178 | -179 | -180 | -180 | -181 | -183 | -183 | -183 | -183 | -182 | -180 | -176 | -172 | -164 | -159 | -159 | -157 | -153 |
| 201904 | LHZ | AR | 720 | -169 | -171 | -172 | -174 | -175 | -177 | -178 | -178 | -179 | -180 | -180 | -181 | -182 | -183 | -183 | -182 | -181 | -180 | -176 | -172 | -164 | -160 | -158 | -156 | -152 |
| 201903 | LHZ | AR | 738 | -171 | -172 | -174 | -176 | -178 | -178 | -179 | -180 | -180 | -180 | -181 | -181 | -182 | -183 | -182 | -182 | -180 | -178 | -175 | -170 | -163 | -157 | -154 | -154 | -150 |
| 201902 | LHZ | AR | 666 | -169 | -170 | -172 | -174 | -175 | -176 | -177 | -178 | -179 | -179 | -179 | -180 | -181 | -181 | -181 | -181 | -180 | -178 | -175 | -170 | -162 | -156 | -153 | -153 | -148 |
| 201901 | LHZ | AR | 737 | -167 | -169 | -170 | -171 | -173 | -174 | -175 | -176 | -177 | -178 | -178 | -179 | -180 | -181 | -180 | -180 | -178 | -177 | -174 | -169 | -162 | -156 | -152 | -151 | -150 |
| 201812 | LHZ | AR | 720 | -170 | -171 | -174 | -174 | -176 | -177 | -178 | -179 | -179 | -179 | -180 | -181 | -182 | -182 | -182 | -181 | -180 | -178 | -174 | -169 | -162 | -155 | -152 | -149 | -147 |
| 201811 | LHZ | AR | 711 | -169 | -171 | -174 | -175 | -176 | -177 | -178 | -179 | -180 | -180 | -180 | -181 | -182 | -182 | -181 | -181 | -179 | -177 | -174 | -168 | -161 | -154 | -151 | -152 | -150 |
| 201810 | LHZ | AR | 312 | -168 | -171 | -172 | -174 | -175 | -177 | -178 | -178 | -180 | -180 | -181 | -181 | -182 | -183 | -182 | -181 | -180 | -178 | -175 | -172 | -164 | -158 | -153 | -151 | -150 |
| 201809 | LHZ | AR | 129 | -167 | -170 | -171 | -173 | -173 | -176 | -177 | -178 | -178 | -180 | -181 | -181 | -182 | -182 | -181 | -181 | -179 | -177 | -173 | -169 | -162 | -156 | -155 | -154 | -150 |
| 201807 | LHZ | AR | 26 | 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 |
| 201806 | LHZ | AR | 42 | 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 |
| 201805 | LHZ | AR | 715 | -168 | -170 | -171 | -173 | -174 | -176 | -177 | -178 | -179 | -180 | -181 | -182 | -183 | -183 | -183 | -183 | -182 | -180 | -176 | -172 | -165 | -160 | -160 | -158 | -156 |
| 201804 | LHZ | AR | 712 | -171 | -173 | -174 | -175 | -177 | -178 | -179 | -179 | -179 | -180 | -181 | -181 | -182 | -183 | -183 | -183 | -181 | -180 | -176 | -173 | -166 | -160 | -157 | -156 | -154 |
| 201803 | LHZ | AR | 743 | -174 | -176 | -178 | -178 | -179 | -180 | -181 | -181 | -181 | -181 | -181 | -181 | -182 | -183 | -183 | -182 | -180 | -178 | -175 | -172 | -164 | -158 | -154 | -152 | -153 |
| 201802 | LHZ | AR | 640 | -170 | -172 | -172 | -174 | -176 | -176 | -177 | -178 | -178 | -178 | -179 | -179 | -180 | -180 | -180 | -180 | -179 | -177 | -174 | -170 | -163 | -155 | -153 | -154 | -151 |
| 201801 | LHZ | AR | 504 | -171 | -172 | -174 | -176 | -176 | -177 | -178 | -178 | -179 | -179 | -179 | -179 | -180 | -181 | -181 | -180 | -179 | -177 | -173 | -168 | -161 | -155 | -151 | -151 | -148 |