Note: Inland Rules regarding sound signals are occasionally different from International Rules.  Inland Rules signal intended action and International Rules signal what you are actually doing.  The following information reflects Inland Rules.  If you travel overseas, you must learn the International Rules.

• One Short Blast - This means that you "intend to leave you on my port side"  if you are meeting or crossing another vessel.   In other words, when you pass the other boat, the left side of your boat will be next to the other boat.  If you are behind another boat and about to pass it, one short blast means that you "intend to pass on
  your starboard side".
• Two Short Blasts - This means that you "intend to leave you on my starboard side in a meeting or crossing situation."  In other words, when you pass the other boat, the right side of your boat will be next to the other
  boat. If you are behind another boat and about to pass it, two short blasts means that you "Intend to overtake
  on your port side.".
• Three Short Blasts - This means that you are backing up, or using "astern propulsion".
• Four Short Blasts - Signals that you intend to leave your dock.  If you need to back out of your docking area,
  you would sound one long blast, and then three short blasts.
• Five Short Blasts - This is the DANGER signal.  Remember, that when you approach another vessel and hear either one or two short blasts, and you both understand their signal and can safely let them do it, then you are required to respond with the same signal in response.  However, if you don't understand their intentions, or feel that their proposed maneuver is dangerous to either vessel, then you are required to sound the DANGER signal.

Note: Another option is to use your VHF radio to reach agreement with another vessel in a meeting or crossing situation. The Rules state that vessels that reach agreement over VHF radio do not need to make the required sound signals.