We may refer to them as air horns, whether they are small and portable or large and permanently installed, the rules regulating collision at sea defines them as a whistle. It is important to remember this because using the nomenclature that is in the navigation rules will make the rule less ominous. There are some references made to the navigation rules, but they are not complete and only partial information is depicted to make a point and it is strongly advised to research this a little further on your own.
Rule 32 of the Navigation Rules provides the following definition, ‘(a) The word whistle means any sound signaling appliance capable of producing the prescribed blasts and which complies with the specifications in Annex III to these Regulations.’
Rule 33 of the Navigation Rules states the whistle requirements for the length of the vessel, ‘(a) A vessel of 12 meters or more in length shall be provided with a whistle, (b) A vessel of less than 12 meters in length shall not be obliged to carry the sound signaling appliances prescribed in paragraph (a) of this Rule but if she does not, she shall be provided with some other means of making an efficient sound signal.’
The requirement to have an efficient sound signal generator such as a boat air horn is not only for one purpose, but it’s intended use is multifold. It is also important to know that if a sound signal is used by another vessel an appropriate response may be required. For example
Rule 34 of the Navigation Rules states ‘(c) When in sight of one another: (i) A power-driven vessel intending to overtake another power-driven vessel shall indicate her intention by the following signals on her whistle:
- (1) One short blast to mean “I intend to overtake you on your starboard side”;
- (2) Two short blasts to mean “I intend to overtake you on your port side”; and (ii) The power-driven vessel about to be overtaken shall, if in agreement, sound a similar sound signal. If in doubt she shall sound the signal prescribed in paragraph (d) of this Rule.
In this situation it is clear there is an appropriate response required from the vessel being overtaken and it is not the middle finger. It is not uncommon to bring our land-based habits with when boating and one that comes to mind is how quickly we become defensive when we hear a blast of a tugboat air horn or any other whistle that is deemed directed at us. Understanding the reason, a whistle is required on board and being aware that it is just an aid in communication one might be prone to using it more frequently as is required by the rules and hopefully receive the appropriate response.
Types of Air Horns
The best air horn for a boat is by no doubt one made for the marine environment and there are also specific requirements of sound levels and frequency ranges required by the navigation rules. For smaller vessels the choices for whistles range from portable horns with disposable air cartridges, permanently mounted electrically driven horns and permanently mounted air horns driven by compresses air from an onboard compressor. Air horn kits
for boats are available that comprise of a single
or double trumpet horn
with a small, dedicated air compressor.
Falcon Safety makes an eco-friendly air-horn
that utilizes ultralow global-warming-potential Aerosol Propellant. You can also find non-flammable air horns
when flammability is a concern such as industrial areas and construction sites. For sporting events, Falcon offers an ozone-free Sports horn
that outperfoms ozone-damaging competitor horns. Portable airhorns for boats are very popular, inexpensive and function tremendously well. Models are available where the air canisters are disposable or refillable by using a small hand pump. Replacement air cartridges for the portable airhorns will keep your horn budget in check. Air Horns are available from reputable manufactures such as ‘Marinco
’, ‘Ancor (Fomerly AFI)
’, and ‘Taylor Made®