2. Bell or gong

(a) Intensity of signal

A bell or gong, or other device having similar sound charac­teristics shall produce a sound pressure level of not less than 110 dBat a distance of 1 metre from it.

(b)Construction

Bells and gongs shall be made of corrosion-resistant material and designed to give a clear tone. The diameter of the mouth of the bell shall be not less than 300 mm for vessels of 20 metres or more in length, and shall be not less than 200 mm for vessels of 12 metres or more but of less than 20 metres in length. Where practicable, a power-driven bell striker is recommended to ensure constant force but manual operation shall be possible. The mass of the striker shall be not less than 3 per cent of the mass of the bell.

3. Approval

The construction of sound signal appliances, their performance and their installation on board the vessel shall be to the satisfaction of the appropriate authority of the State whose flag the vessel is entitled to fly.

ANNEX IV DISTRESS SIGNALS

1. The following signals, used or exhibited either together or separa­tely, indicate distress and need of assistance:

(a) a gun or other explosive signal fired at intervals of about a minute;

(b)a continuous sounding with any fog-signalling apparatus;

(c)rockets or shells, throwing red stars fired one at a time at short intervals;

(d)a signal made byradiotelegraphyor by any other signalling method consisting of the group•••— — —•••(SOS) in the Morse Code;

(e)a signal sent byradiotelephonyconsisting of the spoken word ,,Mayday";

(f)the International Code Signal of distress indicated byN.C.;

(g)a signal consisting of a square flag having above or below it a ball or anything resembling a ball;

(h)flameson the vessel (as from a burning tar barrel, oil barrel, etc.);

(i)a rocket parachute flare or a hand flare showing a red light;

(j)a smoke signal giving off orange-coloured smoke;

(k)slowly and repeatedly raising and lowering arms outstretched to each side;

(1) the radiotelegraph alarm signal;

(m)theradiotelephonealarm signal;

(n)signals transmitted by emergency position-indicating radio beacons.

2. The use or exhibition of any of the foregoing signals except for the purpose of indicating distress and need ofassistance and the use of other signals which may be confused with any of the above signals is prohibited.

3. Attention is drawn to the relevant sections of the International Code of Signals, the Merchant Ship Search and Rescue Manual and the following signals:

(a) a piece of orange-coloured canvas with either a black square and circle or other appropriate symbol (foridentification from the air);

(b)a dye marker.

GUIDANCE FOR THE UNIFORM APPLICATION OF CERTAIN RULES OF THE INTERNATIONAL REGULATIONS FOR PREVENTING COLLISIONS AT SEA, 1972

The following guidance is provided to assist seafarers and all others concerned in the application of certain rules of the International Regu­lations for Preventing Collisions at Sea, 1972:

1. Clarification of the definition, ,,Vessel constrained by her draught", Rule 3 (h)

Not only the depth of water but also the available navigable water width should be used as a factor to determine whether a vessel may be regarded as constrained by her draught. When determining this, due account should also be taken of the effect of a small underkeelclearance on manoeuvrability of the vessel and thus her ability to deviate from the course she is following. A vessel navigating in an area with a small underkeel clearance but with adequate space to take avoiding action should not be regarded as a vessel constrained by her draught.

2.Clarification of the application of the word ..underway", Rule 3 (i)

When applying the definition of the term ,,underway"mariners should also have regard to Rule 35(b)where it is indicated that a ves­sel may be underway but stopped and making no way through the water.

3. Clarification of the implication of the words ,,not to impede" as appearing in Rules 9 (b), (c) and (d), 10 (i) and (j) and 16 (d)

W^hena vessel is required not to impede the passage of another ves­sel, such vessel shall so far as practicable navigate in such a way as to avoid the development of risk of collision. If, however, a situation has developed so as to involverisk of collision, the relevant Steering and Sailing Rules shall be complied with.

4. Clarification of the relation between Rule 10 and the Rules of Part B. Sections II and III

A vessel navigating in or near a traffic separation scheme adopted by the Organization shall, in particular, comply with Rule 10 of the International Regulations for Preventing Collisions at Sea, 1972, to minimize the development of risk of collision with another vessel. The other Rules of the 1972 Collision Regulations apply in all respects, and particularly the Rules of Part B. Sections II and III, if risk of collision with another vessel is deemed to exist.

5. Clarification of the transference within a lane. Rule 10 (b)(i)

It is within the ordinary practice of prudent seamanship and in keepingwith the provisions of Rule 10 of the 1972.Collision Regula­tions that a vessel using a traffic lane may make a transfer within a lane from one side to the other, provided such a transfer is accomplis­hed at as small an angle to the general direction of trafficflow as is practicable.

6. Clarification on the use of inshore traffic zones by small vessels, Rule 10 (d)

To comply with Rule 10 (j)and for reasons of safe navigation a vessel of less than 20 metres in length or a sailing vessel, even when through traffic, may use inshore traffic zones.

7. Clarification of the relation between Rule 18 (d) and the Rules of Part B, Sections II and III

A vessel constrained bvher draught shall, when risk of collision with another vessel in a crossing or head-on situation exists, apply the rele­vant Steering and Sailing Rules as a power-driven vessel. She should, whensliowingthe signals prescribed by Rule 28, have her engines ready for immediate manoeuvre and proceed at a safespeed as required by RuleG.

TABLE OF CONTENS

Page International Regulations for Preventing Collisions at Sea, 1972

Part A — General

Part B— Steering and sailing rules

Section I—Conduct of vessels in any condition of visibility

Section II—Conduct of vessels in sight of one another

Section III—Conduct of vessels in restricted visibility

Part C— Lights and shapes

Part D— Sound and light signals

Part E—Exemptions

Annex I — Positioning and technical details of lights and shapes

Annex II — Additional signals for fishing vessels fishing in close proximity

Annex Ill—Technical details of sound signals appliances

Annex IV—Distress signals

Guidance for the uniform application of certain Rules of the International Regu­lations for Preventing Collisions at Sea, 1972