Core COLREGS Rules — Lookout & Safe Speed
COLREGS Rules 5, 6, 19, and 35 form the regulatory backbone of watchkeeping. The USCG exam tests all four extensively.
Look-Out
Exam FavoriteEvery vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions.
Safe Speed
Exam FavoriteEvery vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropriate to the prevailing circumstances and conditions.
Conduct in Restricted Visibility
A vessel not in sight of another in or near restricted visibility shall proceed at safe speed with engines ready for immediate maneuver, shall not cross a separation scheme, and shall take avoiding action in ample time.
Sound Signals in Restricted Visibility
Power vessel underway making way: one prolonged blast every 2 minutes. Power vessel underway but stopped: two prolonged blasts every 2 minutes. Vessel at anchor: rapid ringing of bell for 5 seconds every minute.
Proper Lookout — All Available Means
Rule 5's requirement to use "all available means" is tested directly. Know every tool that contributes to a proper lookout.
Visual Watch
Dedicated lookout personnel, binoculars, NVGs if equipped, searchlights at night
The helmsman does not count as a dedicated visual lookout. Assign a separate crew member.
Sound / Hearing
Listen for fog signals, vessel horns, breaking water, shoaling sounds, VHF traffic
In fog or restricted visibility, listening is a required element — not optional.
Radar / ARPA
Continuous radar watch at appropriate range scales; ARPA tracks and CPA/TCPA alarms
Radar is part of a proper lookout. Turning it off does not excuse a failure to detect a vessel.
AIS
Automatic Identification System — displays vessel name, MMSI, course, speed, CPA
AIS supplements but does not replace radar. Some vessels do not carry AIS.
VHF Monitoring
Continuous watch on Channel 16 — distress, urgency, Securité calls, and traffic calls
VHF Ch 16 watch is a legal requirement for compulsory-fitted vessels underway.
Depth Sounder
Continuous monitoring in shallow waters — dragging bottom or unexpected shoaling
Rapidly changing depth is a navigational warning — notify master and reduce speed.
Blind Sectors — Exam Alert
A blind sector is any arc of bearing where a vessel's radar or visual lookout is obstructed by the ship's own structure — masts, stacks, cranes, or deckhouses. Every radar installation has documented blind sectors listed in the ship's radar survey.
Blind sectors are a favored exam topic because they represent a gap in Rule 5 compliance. The correct answer: the OOW must maintain visual lookouts covering blind sectors and periodically alter course to sweep those arcs with radar.
OOW Actions for Blind Sectors
- ▸Know your vessel's documented blind sector arcs
- ▸Station visual lookouts to cover those arcs
- ▸Alter course periodically to sweep with radar
- ▸Note radar contacts entering or emerging from blind sectors
- ▸Reduce speed when in traffic near blind-sector arcs
Officer of the Watch — Full Responsibilities
The OOW holds command authority during their watch. These duties are tested on both the OUPV and Master exams.
Navigation Safety
- ▸Maintain the vessel on the ordered course
- ▸Monitor position at appropriate intervals — GPS, visual fixes, and radar
- ▸Identify and avoid all navigational hazards
- ▸Ensure correct charts are in use and updated
- ▸Comply with all applicable COLREGS
Lookout & Traffic
- ▸Maintain a continuous proper lookout — all available means
- ▸Assess all radar contacts for CPA and TCPA
- ▸Take early, substantial action to avoid close-quarters situations
- ▸Monitor VHF Channel 16 continuously
- ▸Respond to Securité and safety broadcasts
Standing Orders & Night Orders
- ▸Read and sign standing orders before the watch
- ▸Read and sign night orders each evening before commencing watch
- ▸Follow all master's instructions precisely
- ▸Call the master when any condition in the orders is met
- ▸Do not deviate from orders without notifying the master
Logbook Entries
- ▸Record position fixes with time and method
- ▸Log all course and speed changes with reasons
- ▸Document weather observations
- ▸Record all vessel encounters and actions taken
- ▸Sign and time all entries — log is a legal document
When to Call the Master
- ▸Visibility drops to prescribed threshold
- ▸Close-quarters situation develops
- ▸Position is in doubt or hazard is near
- ▸Distress call received
- ▸Any machinery or equipment failure
- ▸Any doubt — better to call unnecessarily than not at all
End of Watch
- ▸Conduct a full watch handover briefing
- ▸Do not leave the bridge until properly relieved
- ▸Verify relief OOW is fully briefed and fit for duty
- ▸If relief appears impaired, notify master immediately
- ▸Sign off logbook with time and name
Standing Orders vs. Night Orders
Standing Orders
Written instructions from the master to all officers of the watch that remain in effect throughout the voyage. They set the baseline rules for the watch at all times.
Typical Contents
Night Orders
Specific instructions issued by the master each evening before retiring. They supplement standing orders with voyage-specific conditions for that particular night.
Typical Contents
Watch Handover — Proper Relief Procedure
A proper watch handover is a seamless transfer of situational awareness. The outgoing OOW retains responsibility until the incoming OOW confirms they are fully briefed and fit to assume the watch.
Handover Briefing Checklist
Before Taking the Watch
- ▸Allow eyes to adjust to lighting conditions (especially at night — minimum 15 min dark adaptation)
- ▸Read night orders and standing orders
- ▸Identify all contacts on radar before relieving
- ▸Confirm your own fitness — not fatigued or impaired
If Relief is Unfit
If the incoming OOW appears fatigued, impaired, or insufficiently briefed, the outgoing OOW must not relinquish the watch and must immediately notify the master. Handing over a watch to an unfit officer is a STCW violation and can constitute negligence.
Watchkeeping in Restricted Visibility
Reduce to Safe Speed (Rule 6)
Proceed at a speed that allows you to stop within half the visible range and take proper avoiding action. In dense fog, this may mean near-dead-slow.
Sound Fog Signals (Rule 35)
Power vessel making way: one prolonged blast every 2 minutes. Vessel underway but stopped: two prolonged blasts every 2 minutes. Must be audible — monitor for approaching signals.
Engines Ready for Immediate Maneuver (Rule 19)
Notify engine room to stand by for immediate maneuver. Do not operate with engines in scheduled maintenance or in a configuration that reduces response time.
Post Extra Lookouts
Station additional lookouts forward and on the bridge wings. Lookouts must listen as well as watch — fog signals from approaching vessels may be heard before any contact appears on radar.
Switch Radar to Short Range
Use shorter range scales for maximum detail close-in. Set ARPA alarms for CPA and TCPA thresholds appropriate to current speed and vessel size.
Notify the Master
The master must be called when visibility drops to the threshold in standing orders. If no threshold is stated, call when visibility drops below 3 nautical miles or as conditions dictate.
Rule 19 Governs — Not Give-Way / Stand-On
When vessels are not in sight of each other, give-way and stand-on rules (Rules 12–18) do not apply. Rule 19 applies instead — all vessels take action in ample time.
Do Not Cross Separation Scheme
Vessels in restricted visibility must not cross a traffic separation scheme if they can avoid it. When crossing is unavoidable, cross at right angles to the traffic flow.
Anchor Watch Duties
An anchor watch is legally required when conditions warrant it — dragging anchor is one of the most common maritime incidents. These duties appear on both the OUPV and Master exams.
Monitor position continuously
Take regular bearings on fixed landmarks, check GPS track for any drag, use anchor alarm if GPS allows.
Watch for anchor drag
If bearings change or GPS position moves, anchor may be dragging. Start engines immediately and notify master.
Sound anchor signals in restricted visibility
Rule 35: rapid ringing of the bell every minute. Vessels 100m+ also sound gong aft.
Monitor VHF Channel 16
Keep a continuous watch for distress calls, Securité broadcasts, and Port Control instructions.
Watch for traffic approaching
Anchored vessels are still required to take action if another vessel is approaching and collision risk exists.
Monitor weather changes
Wind shifts and increases may cause the vessel to swing into hazards or another anchored vessel. Log all changes.
Record position and conditions in log
Log position fixes at regular intervals, weather observations, any vessels that swing near or communicate.
Signs of a Dragging Anchor
- ▸Bearings to fixed objects are changing consistently in the same direction
- ▸GPS position is moving away from the drop position
- ▸Anchor chain changes its direction or goes slack
- ▸GPS anchor alarm activates
- ▸Vibration or unusual noise through the hull or chain
- ▸Radar reference point (shore) moves position relative to your vessel
STCW Hours-of-Rest Regulations
Fatigue is a leading cause of maritime accidents. STCW and 46 CFR Part 15 set minimum rest requirements for all watchkeeping personnel. These numbers are tested on the Master exam.
| Period | Minimum Rest | Notes |
|---|---|---|
| Any 24-hour period | 10 hours | Can be split — one block must be ≥ 6 hours |
| Any 7-day period | 77 hours | Minimum continuous rest between reduced periods |
| Emergency exception | 6 hours (min) | Make up rest within 2 days |
Key Rules
- ▸10 hours rest in any 24-hour period
- ▸77 hours rest in any 7-day period
- ▸Rest may be split into 2 periods — one must be ≥ 6 hours
- ▸Rest period between divisions > 1 hour
- ▸Records must be maintained and available for inspection
Violations & Consequences
- ▸Hours-of-rest violations can result in license suspension or revocation
- ▸Master may exceed minimums during emergencies — must record and make up rest within 2 days
- ▸Falsifying rest records is a criminal offense
- ▸Port State Control inspectors check rest records
VHF Watch Requirements
Channel 16 — Bridge Watch
- ▸Compulsory-fitted vessels must maintain a continuous watch on Channel 16 while underway
- ▸Channel 16 is the international distress, safety, and calling channel
- ▸Use Channel 16 only for distress, urgency, safety calls, and initial contact
- ▸After establishing contact, shift to an appropriate working channel
- ▸USCG monitors Channel 16 continuously
Channel 70 — DSC Watch
- ▸Digital Selective Calling — no voice on this channel
- ▸DSC-equipped radios must maintain a watch on Channel 70 for digital distress alerts
- ▸DSC alert automatically transmits vessel MMSI and GPS position
- ▸After DSC alert is received, respond with voice on Channel 16
USCG Working Channels
Securité Broadcasts
Navigation warnings and meteorological warnings are broadcast as Securité (pronounced SAY-CURE-EE-TAY) calls on Channel 16, with details on Channel 22A. The OOW must monitor for and log all Securité broadcasts relevant to the vessel's area. Common topics: drifting hazards, unlit vessels, buoy off station, ice reports.
Official Logbook — Required Entries
The official log is a legal document. It may be subpoenaed in maritime litigation, examined by Port State Control, or reviewed in a USCG investigation. Entries must be accurate, contemporaneous, and legible. Erasures are prohibited — cross out errors with a single line, initial, and write the correct entry.
Required Every Watch
- ▸Position fix — time, coordinates, method (GPS, visual, radar)
- ▸Course steered and any alterations with time and reason
- ▸Speed through water / over ground
- ▸Wind direction and force (Beaufort scale)
- ▸Visibility estimate (miles or description)
- ▸Sea state and swell
- ▸Barometric pressure and tendency
- ▸OOW name and signature — watch change times
When Events Occur
- ▸Any vessel sighting and action taken under COLREGS
- ▸All VHF calls related to safety or navigation
- ▸Distress or urgency signals heard or responded to
- ▸Equipment malfunctions or alarms activated
- ▸Anchoring, mooring, and departure times and positions
- ▸Master notified — time, reason, master's response
- ▸Any injuries to persons on board
- ▸Cargo or hazmat incidents
Exam Tips
Rule 5: 'All available means' is literal
When the exam asks about proper lookout, the answer always includes radar, AIS, VHF, and visual/audio watch. Selecting only 'visual watch' is wrong. The helmsman alone is never a proper lookout.
Rule 19 replaces give-way rules in fog
In restricted visibility where vessels cannot see each other, Rules 12–18 (give-way/stand-on) are suspended. Rule 19 applies to all vessels regardless of type. This is a common trick question.
STCW: 10 hours / 24 hours; 77 hours / 7 days
Memorize both numbers. The split-rest rule (two periods, one ≥ 6 hours) also appears on exams. Emergency reductions must be made up within 2 days.
Standing orders vs. night orders distinction
Exam questions often ask which document covers which situation. Standing orders = permanent, always applies. Night orders = that night only, voyage-specific. Both require OOW signature.
Blind sectors require compensating action
When a blind sector question appears, the answer involves visual lookouts covering the arc AND periodic helm movements to sweep the sector with radar. Neither alone is sufficient.
Call the master — when in doubt
USCG exam questions on OOW responsibility consistently reward calling the master. 'Resolve it yourself without disturbing the master' is almost never the correct answer for a close-quarters or visibility situation.
Frequently Asked Questions
What does COLREGS Rule 5 require for a proper lookout?
COLREGS Rule 5 requires every vessel to maintain a proper lookout at all times using sight, hearing, and all available means appropriate to the prevailing circumstances and conditions. 'All available means' includes visual watch, radar, VHF radio monitoring, ARPA, AIS, and any other technology aboard. A lookout must be a dedicated person — the helmsman alone does not constitute a proper lookout on a vessel underway.
What are the key factors for determining safe speed under Rule 6?
Rule 6 requires every vessel to proceed at a safe speed at all times so that proper and effective action to avoid collision can be taken. Factors include: visibility, traffic density, the vessel's maneuverability (stopping distance and turning ability), background light at night, state of wind/sea/current, navigational hazards nearby, the vessel's draft relative to depth of water, and for radar-equipped vessels — the characteristics and limitations of the radar equipment, range scales in use, sea state effects on radar detection, and the number, location, and movement of vessels detected.
What are the responsibilities of the Officer of the Watch (OOW)?
The OOW is responsible for the safe navigation of the vessel, maintaining a proper lookout, complying with COLREGS, following the master's standing orders and night orders, monitoring weather and navigational hazards, ensuring the helmsman follows the correct course, making required log entries, and notifying the master when required. The OOW must not relinquish the watch until properly relieved and must ensure the relief officer is fully briefed on the vessel's situation.
What is the difference between standing orders and night orders?
Standing orders are permanent written instructions from the master to all OOWs that apply at all times — covering when to call the master, speed restrictions, reporting requirements, and standard watchkeeping procedures. Night orders are specific written instructions issued by the master each evening that apply to that particular night — covering expected weather, planned course changes, specific hazards on the route, and any special instructions. Every OOW must read and sign both documents before commencing a watch.
What are the STCW hours-of-rest requirements for watchkeepers?
Under STCW and 46 CFR Part 15, the minimum rest requirements are: at least 10 hours of rest in any 24-hour period, and at least 77 hours of rest in any 7-day period. The 10-hour rest period may be divided into no more than two periods, one of which must be at least 6 hours. Rest periods may be reduced to no less than 6 hours in any 24-hour period in an emergency at the master's discretion, but the prescribed rest must be made up within two days. Fatigue is a leading cause of maritime accidents; violations can result in license suspension.
What watchkeeping actions are required in restricted visibility?
In or near restricted visibility, the OOW must: post extra lookouts using sight and hearing, reduce speed to safe speed (Rule 6), sound fog signals as required by Rule 35, have engines ready for immediate maneuver (Rule 19), switch on navigation lights, plot all radar targets using ARPA or careful observation, maintain a close watch on VHF Channel 16, notify the master immediately, and comply with COLREGS Rule 19 for vessels not in sight of one another. The vessel must not impede the safe passage of other vessels.
What are the duties of an anchor watch?
An anchor watch officer must: monitor the vessel's position continuously to verify the anchor is holding (check against fixed bearings or GPS track), watch for other vessels swinging into your vessel or dragging anchor, sound the appropriate anchor signals in restricted visibility (Rule 35 — one bell forward, one bell aft every minute for vessels over 100m; a rapid ring of the bell every minute for smaller vessels), maintain a VHF watch on Channel 16, log any changes in weather or position, and be ready to start the engines and alert the master if the anchor drags.
What is a blind sector and how does the OOW address it?
A blind sector is an arc of bearing in which a vessel's radar is blocked by a structure, mast, stack, or other obstruction aboard the vessel. Blind sectors are identified during radar commissioning and documented. The OOW must know the vessel's blind sectors, use visual lookouts to cover those arcs, adjust vessel heading periodically to sweep those sectors with radar if possible, and note any radar contacts that emerge from a blind sector. Target acquisition in a blind sector gap is a common exam scenario — the vessel may have been tracking an unseen approach.
When must the OOW call the master?
The OOW must call the master immediately when: visibility drops below a prescribed limit in standing orders, traffic conditions become complex or potentially dangerous, a close-quarters situation develops that the OOW is uncertain how to resolve, a vessel or object is not responding to expected COLREGS actions, the vessel's position is in doubt or a navigational hazard is close, there is a machinery failure or unusual sound, weather deteriorates significantly, a distress call is received, or any other event occurs that the OOW believes requires the master's judgment. When in doubt, call — calling unnecessarily is never penalized; failing to call can be fatal.
What VHF radio watch requirements apply to commercial vessels?
Under FCC regulations and USCG requirements, compulsory-fitted vessels must maintain a continuous watch on VHF Channel 16 while underway. This is in addition to any working channel in use. DSC-capable radios must also maintain a watch on Channel 70 for digital distress alerts. The OOW or a dedicated radio watch must monitor Channel 16 for distress calls, Securité navigational warnings, and Coast Guard broadcasts. Vessels must not transmit on Channel 16 except for distress, urgency, safety, or calling before shifting to a working channel.
What information must be recorded in the official logbook during a watch?
Required logbook entries include: course steered and any course alterations with times and reasons, speed and engine movements, position fixes with times and the method used, weather conditions (wind, visibility, sea state, barometric pressure), any vessels or hazards sighted and action taken, all VHF communications related to safety, relief of the watch with name of incoming OOW, any accidents, unusual occurrences, equipment failures, medical incidents, and the name and signature of the OOW who maintained the watch. The log is a legal document — entries must be accurate, contemporaneous, and may not be erased.
Related Study Guides
COLREGS Navigation Rules
Complete COLREGS guide — lights, shapes, sound signals, and collision avoidance for the USCG exam.
VHF Marine Radio Guide
Channel assignments, MAYDAY procedure, DSC, Pan-Pan, and FCC licensing requirements.
Man Overboard Procedures
Williamson Turn, Anderson Turn, Pan-Pan calls, hypothermia survival times, and victim recovery.
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