Commercial vessels depend on GMDSS (Global Maritime Distress and Safety System) equipment for emergency communications. Regular inspections prevent equipment failures that could compromise crew safety and lead to costly compliance violations. Maintaining properly functioning radio systems is critical for meeting SOLAS Chapter IV requirements.

Understanding GMDSS Equipment Inspection Requirements

SOLAS Chapter IV regulations require commercial vessels to maintain specific radio equipment based on their operational sea area. An FCC-licensed technician holding a GMDSS Radio Maintainer's License must conduct mandatory inspections annually.

Critical compliance requirement: The inspector cannot be the vessel's owner, operator, master, or employee. After passing inspection, certification must be entered into the ship's log and maintained as required documentation.

Understanding the broader context of maritime safety regulations helps crews appreciate why GMDSS compliance matters. Learn more about what Safety of Life at Sea (SOLAS) actually means and how it underpins all maritime operations.

Equipment requirements vary by sea area but typically include:

• 406 MHz EPIRB (Emergency Position Indicating Radio Beacon)

• VHF radio with DSC capability

• NAVTEX receiver for safety information

• SART (Search and Rescue Transponder)

• Backup power systems

• Two-way VHF radios for survival craft

Before scheduling inspection, gather ship station license, operator licenses, previous inspection reports, radio log books, equipment maintenance records, EPIRB registration, and battery replacement certificates.

GMDSS Equipment Inspection Checklist

VHF DSC Radio

• Test DSC functionality using internal simulation mode

• Verify proper channel selection and frequency accuracy

• Check antenna connections for corrosion or damage

• Confirm distress button operation without transmission

• Verify MMSI programming matches vessel registration

• Test volume controls and speaker output

• Inspect power supply connections and backup power switchover

MF/HF Radio Equipment

• Test frequency synthesis across all bands

• Verify DSC controller operation on designated frequencies

• Check antenna tuner functionality and SWR (Standing Wave Ratio) readings

• Test emergency power supply duration

• Confirm proper grounding connections

• Verify distress frequency monitoring capability

EPIRB (Emergency Position Indicating Radio Beacon)

• Conduct monthly self-test using built-in function

• Inspect hydrostatic release unit for current expiration date

• Check battery expiration (typically 5-year intervals)

• Verify secure mounting and easy manual release

• Confirm EPIRB registration data matches current vessel information

• Inspect for physical damage, cracks, or water intrusion

SART (Search and Rescue Transponder)

• Check battery expiration date

• Verify standby indicator shows ready status

• Inspect mounting bracket and quick-release mechanism

• Test self-test function per manufacturer instructions

• Confirm waterproof seal integrity

NAVTEX Receiver

• Verify reception of scheduled broadcasts

• Check message filtering settings match vessel area

• Test alarm functionality for safety messages

• Verify backup power operation

• Confirm paper or memory capacity for message storage

Vessel Radio Inspection: Testing Procedures

Daily Tests

• Perform VHF DSC capability tests using internal simulation mode

• Monitor NAVTEX receiver operation

• Check battery charge indicators on portable equipment

• Record all results in radio log book

Maintaining proper radio log documentation is critical for demonstrating compliance. Reference how to keep a captain's log book for best practices on documenting all daily, weekly, and monthly tests.

Weekly Tests

• Test VHF DSC using actual test calls (when within range of coast station)

• Check EPIRB self-test indicators and visual confirmation lights

• Inspect all equipment for physical damage

• Verify battery status on all portable devices

Monthly Tests

• Conduct EPIRB self-test function (checks battery voltage, output power, frequency)

• Test SART functionality using built-in test mode

• Verify battery status and check expiration dates for upcoming replacements

• Review and update radio log book with all test results

Reserve Power System Verification

Reserve power requirements depend on vessel construction date per SOLAS regulations:

• Ships built before February 1, 1995: Six-hour reserve capacity required

• Ships built after February 1, 1995: One-hour reserve capacity may apply

Maintenance requirements:

• Check battery capacity at intervals not exceeding 12 months

• Test automatic switchover from main to reserve power

• Verify charging systems maintain proper voltage levels

• Inspect battery terminals for corrosion and secure connections

If battery testing hasn't occurred within the past 12 months, perform capacity testing immediately during inspection.

Maritime Communication Systems Documentation

Maintain complete records for inspector review:

✓ Radio log book with daily, weekly, and monthly test entries
✓ Equipment maintenance records showing servicing dates
✓ Battery replacement certificates with installation dates
✓ EPIRB and SART annual test reports
✓ Shore-based maintenance agreements
✓ Operator license renewals and training certificates

The inspector verifies certification stamps match installed equipment and confirms compliance with 47 CFR Part 80 Subpart W maintenance intervals. Consult SOLAS consolidated regulations for authoritative carriage and documentation requirements specific to your vessel class and operational area.

Common Inspection Failures to Prevent For GMDSS Equipment

Avoid these frequent compliance issues before inspection:

• Expired EPIRB or SART batteries

• Missing or incomplete radio log entries

• Incorrect MMSI programming in DSC equipment

• Failed reserve power capacity tests

• Outdated or unregistered EPIRB information

• Insufficient operator licensing documentation

• Corroded antenna connections affecting transmission quality

• Non-functional distress buttons or emergency activation systems

Address these items during routine maintenance rather than during scheduled inspections.

2024 GMDSS Modernization Requirements

Effective January 1, 2024, significant amendments to SOLAS Chapter IV apply to all vessels at their first Safety Radio Survey following this date.

Key changes:

• VHF-EPIRBs no longer accepted for Sea Area A1 coverage (satellite EPIRBs now required)

• Iridium recognized as approved satellite provider alongside Inmarsat

• Updated performance standards for radio equipment

• Enhanced cybersecurity requirements for GMDSS systems

Review updated Paris MoU (Port State Control) guidelines for current inspection criteria and implementation dates. Additional maritime equipment and safety regulations context available in modern ship navigation equipment overview.

Maintaining Compliance Between Inspections

Regular equipment testing prevents inspection failures and ensures operational readiness during emergencies.

Best practices:

• Assign qualified crew members to perform routine checks and document results consistently

• Schedule battery replacements before expiration dates

• Maintain service agreements with authorized technicians for annual EPIRB testing and equipment calibration

• Keep equipment manuals accessible to bridge team

• Train crew on proper testing protocols using available training resources

• Verify MMSI and registration data remains current after vessel ownership transfers or documentation updates

• Review equipment settings after software updates or system changes

Ensure two crew members hold valid GMDSS Radio Operator's Licenses. One must be available to serve as a dedicated radio operator during distress situations.

Ensuring Ongoing GMDSS Compliance

GMDSS equipment reliability directly supports vessel safety and regulatory compliance. Annual inspections by FCC-licensed technicians, combined with consistent crew testing and maintenance, ensure your maritime communication systems remain operational when needed most.

Proper documentation, current batteries, functional equipment, and trained operators form the foundation of GMDSS compliance. Address maintenance issues promptly and maintain comprehensive records throughout the year.

For detailed guidance on GMDSS equipment compliance and inspection requirements, consult your flag state administration and current FCC regulations (47 CFR Part 80).

Related Resources

• What is Safety of Life at Sea (SOLAS)?

• How to Keep a Captain's Log Book

• Navigation Equipment Used on Modern Ships

• SOLAS Consolidated Edition 2024

American Nautical Services – Supporting maritime safety and compliance since 1977.

FAQs

Q1: How often must GMDSS equipment be inspected?

A: Commercial vessels require annual inspections by an FCC-licensed technician. Daily, weekly, and monthly crew-conducted tests must be performed and documented in the radio log book.

Q2: Can vessel crew perform GMDSS inspections?

A: No. FCC regulations require inspections by licensed technicians holding a GMDSS Radio Maintainer's License. The inspector cannot be the vessel's owner, operator, master, or their employee.

Q3: What happens if equipment fails inspection?

A: Failed equipment must be repaired or replaced before the vessel can receive certification. The inspector documents deficiencies, and re-inspection is required after corrections are completed.

Q4: How long are EPIRB batteries valid?

A: EPIRB batteries typically expire after 5 years from manufacture or following emergency use. Check expiration date labels and replace before expiration to maintain compliance.

Q5: What documentation must be onboard during inspection?

A: Vessels must have a ship station license, operator licenses, radio log book, equipment maintenance records, EPIRB registration certificates, previous inspection reports, and battery replacement certificates available.