What can the operator do to adjust the...

🔍 Key Concepts

• GMDSS VHF DSC (Digital Selective Calling) alarm behavior for different message priorities (Distress, Urgency, Safety, Routine) • What the operator is allowed to change (volume/tones/acknowledgment) versus what is mandatory by regulation • Which types of alerts on a DSC radio must not be able to be turned off for safety reasons

💭 Think About

• Think about why the GMDSS rules require strong audible alarms for certain messages. Which message priorities are considered the most critical to safety of life at sea? • Ask yourself: Is it reasonable or permitted for the operator to completely silence the radio for those most critical messages? • Consider whether all four priorities (Distress, Urgency, Safety, Routine) are treated exactly the same, or whether some must always trigger an audible alarm that cannot be disabled.

✅ Before You Answer

• Verify which message priorities are life‑critical and therefore must generate a strong audible alarm • Check whether Distress and Urgency can legally have their alarms disabled or silenced by the operator • Confirm if the operator’s control over the audible alarm (e.g., volume, muting) applies equally to all four priorities or if there is an exception for the highest priorities

What can the operator do to adjust the audible alarm?

The operator can choose to disable the audible alarm.

VHF DSC units only have visual alarms.

The alarm cannot be disabled for Distress and Urgency messages.

The audible alarm control has the same indication for all four message priorities.

🔍 Key Concepts

💭 Think About

✅ Before You Answer