2 Chapter 2
- Make changes to paragraph 2.3 as follows (new text is underlined, deletions
struck) and renumber the paragraphs accordingly:
Vessels Ships communicate with coast radio stations and with each other on maritime frequencies available in MF, HF and VHF bands. The GMDSS (Global Maritime
Distress and Safety System) is mandatory for all SOLAS ships from 1999. Volume I,
Appendix G provides more information on carriage requirements for SOLAS ships.
2.3.3. Use of 500 KHz for Morse Code distress, safety and calling transmissions has historically been popular, and has often overcome language barriers. However with the event of more advanced technologies, use of 500 KHz is decreasing. As of February 1999, international requirements to have this capability aboard ships will cease. Silence periods on this frequency are observed for three minutes twice an hour, beginning at 15 and 45 minutes past each hour, to facilitate reception of distress calls, and in the and in the last 15 seconds of each period to announce distress, urgency, or safety broadcasts.
2.3.3 The frequency 2182
KHzkHz, an international maritime voice distress, safety and
calling frequency may be also available in SAR aircraft.
Silence periods on this
frequency are observed for three minutes twice an hour, beginning on the hour and
at 30 minutes past each hour, to facilitate reception of distress calls.
2.3.5 MF Radio Alarms. A number of coast and ships stations are equipped to transmit the radio alarm signal on 500 KHz radiotelegraphy or 2182 KHz radiotelephony by means of an automatic signal-generating device. The signal actuates automatic devices giving an alarm to attract attention of operators not maintaining an aural watch, and is followed by the Morse signal "SOS SOS SOS" on 500 KHz radiotelegraphy and the spoken words "MAYDAY MAYDAY MAYDAY"on 2182 KHz. a) The telegraphy distress alarm consists of a series of twelve dashes sent in one minute, the duration of each dash being four seconds, and the duration of the interval between consecutive dashes being one second. b) The radiotelephony alarm consists of two audio-frequency tones transmitted alternately (similar in sound to a two- tone siren used by some ambulances). It is sent continuously for a period lasting from 30 seconds to a minute. A long continuous tone at the end of the alarm signifies that the signal originated from a coast station and not a ship station. c) Radio alarms may only be used to announce: That a distress call or message is about to follow; or That transmission of an urgent meteorological warning; or The loss of a person overboard, when help of other vessels is required and cannot be satisfactorily obtained by use of the urgency signal only. d) Tests of radio alarms are prohibited." d) Tests of radio alarms are prohibited."