DSC PROCEDURES FOR VHF AND MF

Transmission of DSC distress alertA distress alert should be transmitted if, in

the opinion of the Master, the ship requires immediate assistance.

A DSC distress alert should include the ship’s last known position and time in UTC.

The DSC alert is transmitted as follows:Tune the transmitter to the DSC distress channel

(MF-2187.5 kHz, VHF channel 70)If time permits, select the nature of distressThe ship’s last known positionTime in UTCType of subsequent distress communicationTransmit the DSC distress alertPrepare for the subsequent distress traffic by

tuning the radiotelephony transmitter to the distress traffic channel in the same band. (2182 kHz on MF,

channel 16 on VHF while waiting for the distress acknowledgement.

Actions on receipt of a distress alertWait for the coast station to acknowledge first.If the alert is still continuing, acknowledge the

distress alert and inform Coast Station or RCCTune the radiotelephony receiver to the distress

traffic in the same band.

Transmission of a DSC distress relayTune the transmitter to the DSC distress channel

(MF-2187.5 kHz, VHF channel 70)Select the distress relay call formatKey in - All ships call (VHF); Geographic Area

Call (MF/HF); or Coast Stations MMSI.Station in distress MMSI, if known.The nature of distress, position and time if

known.Type of distress communicationTransmit the DSC distress relay callPrepare for the distress traffic while waiting for

the acknowledgement.

Cancellation of an inadvertent distress alert

A station transmitting an inadvertent distress alert shall cancel the distress alert:

Immediately cancel the distress alert aurally over the associated telephony distress channel

Monitor the associated telephony distress traffic channel and respond to any communications concerning that distress alert as appropriate.

All stations All stations All stationsThis is BRUNITA, BRUNITA, BRUNITA CALLSIGN

LKFE, MMSI 257666000In position 14°34’ N 120° 23EPlease cancel my distress alert of 23 Feb,

0400H UTCDate and Time 23 of Feb., 0500H UTCMaster MV BRUNITA Callsign LKFE

Transmission of urgency messagesThe broadcast of an urgency message is carried

out on a DSC urgency call:Tune the transmitter to the DSC distress channel

(MF-2187.5 kHz, VHF channel 70)Key in - All ships call (VHF) or Geographic Area

Call (MF/HF) or individual callThe category of call (urgency)Working frequency or channelType of communicationTransmit the DSC urgency call

Transmission of safety messagesThe broadcast of a safety message is carried out on

a DSC safety call:Tune the transmitter to the DSC distress channel

(MF-2187.5 kHz, VHF channel 70)Key in - All ships call (VHF) or Geographic Area

Call (MF/HF) or individual callThe category of call (safety)Working frequency or channelType of communicationTransmit the DSC safety call

DISTRESS

URGENCY

SAFETY

IMPORTANT SHIP TRAFFIC

ROUTINE

Public CorrespondenceThe Public correspondence is carried out on a DSC

routine call:Tune the transmitter to the DSC distress channel

(MF-2187.5 kHz, VHF channel 70 or the coast station’s working frequency)

Key in the MMSI of a particular station to be called

The category of call (routine)Working frequency or channelType of communicationTransmit the DSC routine call

Repeating a DSC CallDSC Call for public correspondence may be

repeated on the same or another DSC channel/frequency, if no acknowledgement is received within 5 min.

Further call attempts should be delayed at least 15 min, if acknowledgement is still not received.

DSC Test call

DSC PROCEDURES FOR HF

Transmission of DSC distress alertDSC distress alert should be sent to coast

stations A3 and A4 sea areas on HF.Propagation characteristics of HF radio waves

should be taken into account in choosing HF bands for transmission of DSC distress alert.

8414.5 kHz may in many cases be an appropriate first choice.

Transmission of the DSC distress alert in more than one HF band will normally increase the probability of successful transmission..

The HF DSC distress alertTune the transmitter to the HF DSC distress

frequency (4207.5, 6312, 8414.5, 12577, 0r 16804.5 kHz)

If time permits, select the nature of distressThe ship’s last known positionTime in UTCType of subsequent distress communicationTransmit the DSC distress alertPrepare for the subsequent distress traffic by tuning

the radiotelephony transmitter to the appropriate distress traffic frequency in the same band while waiting for the distress acknowledgement.

HF Distress and Safety calling Frequencies

DSC (kHz) Telephony (kHz) Radiotelex (kHz)

4297.5 4125 4177.56312.0 6215 6268.08414.5 8291 8376.5

12577.0 12290 12520.016804.5 16420 16695.0