| NOS |
NIMA |
|
IHO/Foreign NIMA Charts |
| General |
 |
 |
Position of fog signal (type of fog signal not stated) |
 |
| Types of Fog Signals, with Abbreviations |
| GUN |
Explosive |
Explos |
| DIA |
Diaphone |
Dia |
| SIREN |
Siren |
Siren |
| HORN |
Horn (Nautophone, reed, tyfon) |
Horn |
| BELL |
Bell |
Bell |
| WHIS |
Whistle |
Whis |
| GONG |
Gong |
Gong |
| Examples of Fog Signal Descriptions |
 |
 |
Siren at a lighthouse, giving a long blast followed by a short one (N), repeated every 60 seconds |
 |
 |
 |
Wave-actuated bell buoy |
 |
 |
 |
Light buoy, with horn giving a single blast every 15 seconds, in conjunction with a wave-actuated whistle |
 |
| ‡ The fog signal symbol may be omitted when a description of the signal is given. |
| Supplementary National Symbol |
| Mo |
|
Morse Code fog signal |
|
