Engine room watchkeeping

In short

Engine room watchkeeping is the organised, continuous supervision of a ship's propulsion and auxiliary machinery by a qualified engineer officer who is in charge of the machinery space, responsible for its safe operation, record keeping and response to alarms and emergencies. It is governed internationally by STCW 1978 as amended (Chapter VIII and Code Part A-VIII/2 Part 3) and in India by the Merchant Shipping Act, 2025 (in force 15 March 2026; it repealed the 1958 Act) with the M.S. (STCW for Seafarers) Rules, 2014, continued under it, administered by the Directorate General of Shipping (renamed the Directorate General of Maritime Administration, DGMA, in 2026). It is examined in every Indian maritime university paper on watchkeeping and marine engineering practice, in the DG Shipping Class IV/MEO oral examinations, and is the single most asked practical area in interviews for Junior Engineer and Fifth Engineer posts with SCI, Great Eastern Shipping, Essar, Anglo-Eastern, Fleet Management, Synergy and V.Ships. Unlike ship construction or firefighting, which deal with structure and emergency response, watchkeeping deals with the routine discipline that keeps the plant running and makes emergencies rare.

Explained

What a watch is and who keeps it

• A watch is a defined period during which a named officer holds charge of the machinery space; the classic rotation is four hours on, eight off: 0000–0400 and 1200–1600 (Third/Fourth Engineer), 0400–0800 and 1600–2000 (Second Engineer traditionally), 0800–1200 and 2000–2400 (Fourth/Third Engineer).
• The Chief Engineer is the head of department, does not normally keep a watch, and issues standing orders (permanent instructions for the voyage) and night orders (specific instructions for a particular night, signed by each engineer on reading).
• The Second Engineer is responsible for the day-to-day running and maintenance of machinery and for the watch schedule; the engineer officer of the watch (EOOW) is the Chief Engineer's representative, with authority over everyone in the space.
• Watch ratings — motorman, oiler, wiper, fitter — assist with soundings, purifier changeovers, cleaning and standby duties; the engine rating forming part of a watch must be certificated under STCW Regulation III/4.
• Manning is by the ship's Safe Manning Document; the minimum rest hours (10 hours in any 24, 77 in any 7 days, split into no more than two periods, one of at least 6 hours) come from STCW and MLC 2006, and are implemented in India through section 57 of the Merchant Shipping Act, 2025 and the Merchant Shipping (Maritime Labour) Rules, 2026, which replaced the M.S. (Maritime Labour) Rules, 2016. Note that these hour figures are the current standard but may be amended.

Taking over and handing over a watch

1. The relieving engineer must be fully awake and fit — never relieve or hand over to anyone apparently unfit, and report such a case to the Chief Engineer.
2. Read the log book, bell book, standing and night orders and any new work permits or defect notices before accepting the watch.
3. Walk round the space with the outgoing engineer; note the mode of operation (manoeuvring, full away, UMS), machinery running and on standby, and anything under repair or isolated.
4. Check bilge, bunker, settling, service and fresh water tank levels, running hours, fuel in use (HFO or MGO) and whether an ECA/sulphur changeover is pending.
5. Confirm all alarms are in service and none are suppressed, inhibited or taped over; note any override in the log with the reason.
6. Hand over does not happen during an alarm, a critical operation (bunkering, tank transfer, manoeuvring, purifier changeover) or any emergency — complete or stabilise it first.
7. The relieving officer says clearly "I have the watch"; until then the outgoing engineer remains responsible.

Routine duties during the watch

• Rounds: at least hourly, following a fixed route so nothing is missed — main engine, auxiliary engines, boiler, purifiers, air compressors, shaft tunnel, steering gear compartment, workshop and bilges.
• At each machine use the five senses: look (leaks, levels, smoke, colour of exhaust), listen (knocking, cavitation, bearing noise), feel (vibration, bearing temperature by hand on the housing, never on moving parts), smell (burning oil, scavenge fire, electrical), read (gauges against the previous hour's figures).
• Log entries are made hourly: main engine rpm, fuel rack/index, scavenge air pressure and temperature, exhaust gas temperatures per unit, jacket cooling water inlet/outlet temperatures and pressure, lube oil pressure and temperature, turbocharger rpm, thrust bearing temperature, bunker consumption, generator load and kWh, boiler pressure and water level.
• Trend watching matters more than absolute numbers: a slow rise in one unit's exhaust temperature or a drop in cooling water pressure is the real finding.
• Bilges are kept dry; bilge wells are sounded and pumped out through the oily water separator at 15 ppm only outside special areas and with the OWS working, and every operation entered in the Oil Record Book Part I (MARPOL Annex I, Regulations 15 and 17). Discharge of oil inside Indian waters is also an offence under the pollution Part of the Merchant Shipping Act, 2025 (sections 131-143, notably section 133 on control of discharge) with the Merchant Shipping (Prevention of Pollution by Oil from Vessels) Rules, 2026, and under the Environment (Protection) Act, 1986.
• Purifiers and filters: check back-pressure, sludge discharge, feed temperature (around 98 °C for HFO), de-sludge timing and changeover of duplex filters.
• Soundings and transfers: sound tanks, transfer fuel to settling and service tanks only with the correct valve line-up and never leave a transfer unattended; overflow tank high-level alarm must be live.
• Housekeeping: mop oil spills immediately, keep gratings and escape routes clear, tools returned, no rags near hot surfaces — the commonest cause of an engine room fire is oil on a hot surface above 220 °C.

Communications, bridge orders and manoeuvring

• The engine telegraph transmits bridge orders; in bridge control the bridge moves the lever directly, in engine room control the EOOW matches the telegraph and acknowledges, and in emergency/local control the engine is operated at the side of the engine from the local station.
• Every telegraph order, its time and the engine's response are entered in the bell book (movement book), which is the legal record in any collision or grounding enquiry; it is later transcribed into the engine room log.
• Before arrival/departure (one hour notice typical): test steering gear (required within 12 hours before departure under SOLAS Chapter V Regulation 26), change over from HFO to MGO where required, start the second steering gear pump, raise air bottle pressure to full (about 30 bar), test ahead and astern movements, bring the standby generator and standby pumps to automatic, test the telegraph, engine room telephone and emergency stops.
• During manoeuvring the EOOW stays at the control station, does not leave the space, and records every movement; the Chief Engineer is normally present for critical manoeuvres.
• Report to the bridge immediately any reduction in manoeuvring capability, steering gear fault, impending slowdown or shutdown, blackout, or anything that will affect speed or power.

Unattended machinery space (UMS) operation

• A UMS-notated ship (class notations such as IRS UMS, LR UMS, DNV E0) is designed so that the space may be left unattended, with machinery alarms extended to the bridge and to the duty engineer's cabin and public spaces.
• Requirements (SOLAS Chapter II-1 Part E): automatic bilge level alarm and pumping, fire detection in the space, automatic standby start of essential pumps, automatic start of the emergency generator, machinery alarms grouped and repeated outside the space, two-way communication between bridge, control room and duty engineer's cabin, and a dead man alarm (engineer's call/safety alarm) that raises a general call if the engineer entering the space does not reset it periodically.
• Before going UMS: full round, bilges dry, no leaks, all standby machinery on auto, alarms tested and none inhibited, purifiers set, duty engineer's name posted, dead man alarm set, filters cleaned, the space secured and watertight doors closed.
• Duty engineer on UMS: carries the alarm/portable radio, never enters the space alone without informing the bridge and resetting the dead man alarm, does rounds at least morning and evening, and attends any alarm.
• Advantages: better use of manpower, engineers work day-work on planned maintenance, fewer men exposed to noise above 85 dB(A) and heat. Limitations: total dependence on sensors and alarm integrity, slow human response to a developing fault, risk of nuisance alarms being inhibited, and an engineer alone in the space is a safety hazard.

Alarms, emergencies and abnormal situations

• Priority on any alarm: safety of people first, then the ship, then the machinery. Acknowledge, identify, verify locally (never trust a single sensor), act, inform the bridge and the Chief Engineer, record.
• Main engine lube oil low pressure → the engine will slow down/shut down automatically; check level, filter back-pressure, pump, and whether a standby pump started. Never override a shutdown except on the Master's written order for safety of navigation, and log it.
• Blackout: emergency generator should start automatically within 45 seconds and supply emergency lighting, steering gear, fire pump and essential services; restore main power by starting a generator on air/battery, close breaker, restart pumps in order (cooling, lube oil, fuel), restart the main engine, inform the bridge, record the cause.
• Scavenge fire: falling rpm and rising exhaust temperature on one unit, hot scavenge trunk, smoke from drains — slow down or stop, cut fuel to that unit, close scavenge drains, stop auxiliary blowers, cool the trunk, extinguish by the fixed smothering connection, and never open up until cool.
• Crankcase oil mist alarm: indicates a hot spot and the risk of a crankcase explosion — stop the engine, do not open the doors for at least 20–30 minutes, keep the lube oil pump running, then investigate by feeling for a hot bearing.
• Fire in the engine room: sound the alarm, inform the bridge, attack with portable means if small, otherwise stop fans and machinery, shut quick-closing valves and skylights, account for all personnel, and only then release the fixed gas system from outside.
• Flooding: identify the source, start bilge/general service pumps, close valves, inform the bridge, assess stability implications.
• Permit to work is required for entry into enclosed spaces, hot work, work on electrical equipment and aloft; isolate and lock out/tag out before any work on machinery.

Records, codes and the Indian framework

• Documents the EOOW maintains or signs: engine room log book, bell/movement book, Oil Record Book Part I, soundings book, running hours and planned maintenance entries, sludge and garbage records, night order acknowledgement, defect list and work permits. Entries are in ink, never erased — a wrong entry is struck through, corrected, initialled.
• STCW Code A-VIII/2 Part 3 sets the principles of a machinery watch; A-VIII/1 fitness for duty and rest hours; B-VIII/2 guidance. The ISM Code (SOLAS Chapter IX) requires the company's SMS to cover watchkeeping procedures, and the MARPOL annexes govern discharges.
• In India: the Merchant Shipping Act, 2025 (which repealed the 1958 Act from 15 March 2026), with the M.S. (STCW for Seafarers) Rules, 2014 continued under it and the new Merchant Shipping Rules, 2026 on survey, safety and pollution; the DG Shipping (now DGMA) issues Certificates of Competency (MEO Class IV, III, II, I) and Engine Watch Rating certificates; MMD (Mercantile Marine Department) offices at Mumbai, Chennai, Kolkata and Kochi conduct the examinations; Indian Register of Shipping (IRS) rules give the UMS and automation notations; Port State Control and flag inspections check log books, alarm status and rest-hour records.
• Drug and alcohol policy: STCW sets a limit of 0.05% blood alcohol or 0.25 mg/l in breath; most Indian-crewed fleets operate a stricter zero-alcohol shipboard policy.

Key points

• EOOW - engineer officer of the watch, the Chief Engineer's representative in the machinery space, responsible for safety and records.
• Standing orders - permanent written instructions from the Chief Engineer; night orders are nightly, signed by each engineer.
• Bell book - legal record of every telegraph order and engine response during manoeuvring.
• Handover rule - never hand over during an alarm, emergency or critical operation, nor to an officer apparently unfit.
• Hourly rounds - fixed route, five senses, compare readings with the previous hour; trends matter more than absolutes.
• 15 ppm rule - bilge water overboard only through a working oily water separator with 15 ppm alarm and auto-stop, logged in Oil Record Book Part I.
• UMS - unattended machinery space; alarms extended to bridge and duty engineer's cabin, dead man alarm, automatic standby starts.
• Dead man alarm - raises a general call if the engineer in the space does not reset it within a set interval.
• Emergency generator - must start automatically and be on load within 45 seconds of a blackout.
• Steering gear test - within 12 hours before departure (SOLAS V/26), plus communication and emergency steering drill.
• Slowdown and shutdown - automatic protections on lube oil pressure, jacket water temperature, overspeed, oil mist; overridden only on the Master's order and logged.
• Scavenge fire signs - rising exhaust temperature and hot trunk on one unit with falling rpm; smother, do not open hot.
• Crankcase explosion - oil mist from a hot spot; stop, wait 20–30 minutes before opening doors, keep lube oil circulating.
• Rest hours - minimum 10 hours in 24 and 77 in 7 days under STCW/MLC, recorded and inspected.
• STCW A-VIII/2 Part 3 - the governing watchkeeping provision; ISM Code requires documented company watch procedures.
• DG Shipping - Indian regulator; MEO Class IV is the first engineer officer COC, obtained through MMD oral examination.
• No overriding alarms - an inhibited or taped-over alarm is a detainable deficiency at Port State Control.
• Report to bridge - any loss of manoeuvrability, power, steering or speed, immediately and without being asked.

Formulas and examples

Example 1 — Daily fuel consumption from log readings. A two-stroke main engine runs at 10,500 kW with an SFOC of 175 g/kWh.

• Fuel per hour = 10,500 × 175 = 1,837,500 g/h = 1.8375 t/h.
• Per day = 1.8375 × 24 = 44.1 tonnes/day.
• Over a 2,400 nautical mile passage at 14 knots: time = 2,400/14 = 171.43 h = 7.143 days → fuel = 44.1 × 7.143 ≈ 315 tonnes, plus auxiliary and boiler consumption.

Example 2 — Checking the hourly log for a developing fault. Unit exhaust temperatures at 0400 are 365, 370, 368, 372, 366, 369 °C. At 0600 the same units read 366, 371, 369, 398, 367, 370 °C.

• Mean of the five normal units at 0600 = (366 + 371 + 369 + 367 + 370)/5 = 1,843/5 = 368.6 °C.
• Unit 4 is 398 − 368.6 = 29.4 °C above the mean, against about 7 °C spread earlier.
• Action: a single unit running hot with others unchanged points to a fuel injector/valve problem or late injection; check fuel pump index, injector opening pressure and the exhaust valve, inform the Chief Engineer, and log the finding. A rise in all units together would instead suggest fouled air coolers, high scavenge temperature or turbocharger fouling.

Example 3 — Bilge discharge legality. The bilge holding tank contains 6.0 m³ of oily water. The OWS is rated 2.5 m³/h with a 15 ppm monitor; the ship is 60 nautical miles from the nearest land, en route at 12 knots, not in a special area.

• Time to process = 6.0/2.5 = 2.4 hours (2 h 24 min).
• Distance covered meanwhile = 12 × 2.4 = 28.8 nautical miles — the ship remains well clear of land throughout.
• Legality: permitted under MARPOL Annex I Regulation 15 because the ship is en route, the 15 ppm equipment is in operation with automatic stopping, and the area is not special. Entry required in Oil Record Book Part I, Code D (non-automatic discharge of bilge water; Code E if the discharge is automatic) with start/stop times, tank identity and quantity. Note that regional rules (for example in the Indian EEZ or a declared special area such as the Gulf of Aden/Red Sea) can be stricter.

Example 4 — Air bottle capacity for starting. Two air bottles of 3.0 m³ each at 30 bar; the engine needs 0.45 m³ of free air per start and the rules require 12 consecutive starts for a reversible engine without replenishment.

• Usable pressure band 30 → 10 bar = 20 bar, so free air available per bottle ≈ 3.0 × 20 = 60 m³ (treating gauge pressure ratio to atmospheric as 1 bar ≈ 1 m³ per m³ of bottle).
• Two bottles = 120 m³ free air → starts available = 120/0.45 ≈ 267 — far above the 12 required, which is why the EOOW's real duty is to keep compressors and drains working rather than to count starts.
• Practical check before manoeuvring: both bottles at full pressure, drains blown through, both compressors on auto, one bottle kept isolated as a reserve.

Example 5 — Rest-hour compliance. An engineer keeps 0000–0400 and 1200–1600 watches, plus 1600–1800 maintenance on one day.

• Work = 4 + 4 + 2 = 10 hours; rest = 24 − 10 = 14 hours, in periods 0400–1200 (8 h) and 1800–2400 (6 h).
• Compliant: 14 hours ≥ 10 hours, in two periods, one of at least 6 hours. If instead he is called out 2100–2300 for a purifier, rest becomes 8 + 3 + 1 = 12 hours but in three periods — still 12 hours total, but the "not more than two periods" condition is breached and must be recorded as a non-conformity with compensatory rest.

Where it is used

• Merchant shipping: Junior/Fifth/Fourth Engineer on tankers, bulk carriers, container ships and gas carriers with SCI, Great Eastern Shipping, Essar Shipping, Seven Islands, and crewing managers Anglo-Eastern, Fleet, Synergy, V.Ships and Wallem.
• Offshore and dredging: OSVs, drill ships, Dredging Corporation of India vessels, where watchkeeping extends to dynamic positioning power management.
• Indian Navy and Coast Guard: marine engineering officers keep machinery control room watches on similar principles with naval procedures.
• Inland and coastal operations: Inland Waterways Authority of India vessels, port tugs and ferries, where the engineer often keeps watch single-handed under local rules.
• Shore roles built on this experience: superintendents and technical managers in ship management offices, class surveyors with IRS, MMD/DG Shipping surveyors, marine insurance and P&I surveyors, and simulator instructors at IMU, TMI, AMET and the Marine Engineering and Research Institute, Kolkata.
• Power and process plants: the same discipline — hourly logs, rounds, handover, standing orders, permit to work — is used in captive power plants and refineries, so the skill transfers to shore shift-engineer jobs.

Interview questions

• Q: What is the first thing you do on taking over a watch? A: Read the log, bell book and standing/night orders, then do a full round with the outgoing engineer and confirm all alarms are in service before accepting the watch.
• Q: Can you take over a watch when an alarm is active? A: No — the outgoing engineer must stabilise or clear the situation first; handover during an alarm, an emergency or a critical operation is not permitted.
• Q: What is a dead man alarm and why is it fitted? A: A timer in a UMS space that must be reset periodically by the engineer inside; if not reset it raises a general call, protecting an engineer who has collapsed or been injured while working alone.
• Q: Before going UMS, what do you check? A: Full round completed, bilges dry and no leaks, all standby machinery on auto, alarms tested with none inhibited, dead man alarm set, duty engineer posted, and the bridge informed.
• Q: What are the signs of a scavenge fire and your action? A: Rising exhaust temperature and hot scavenge trunk on one unit with falling rpm and smoke from drains; slow down or stop, cut fuel to that unit, close drains, stop blowers, smother through the fixed connection and do not open until cool.
• Q: Oil mist detector alarm — what do you do? A: Stop the engine immediately, keep the lube oil pump running to cool the hot spot, and wait at least 20–30 minutes before opening crankcase doors, since early opening can admit air and cause a secondary explosion.
• Q: Under what conditions may you pump bilges overboard? A: Through a working oily water separator below 15 ppm with automatic stopping, while en route, outside special areas and with the Chief Engineer's permission — every operation logged in Oil Record Book Part I.
• Q: Would you ever override a main engine shutdown? A: Only on the Master's instruction where stopping would endanger the ship's safety of navigation, with the Chief Engineer informed and the override and reason entered in the log.
• Q: What happens on a blackout and in what order do you restore? A: The emergency generator starts automatically within 45 seconds; then start a generator on starting air or battery, close the breaker, restart cooling, lube oil and fuel pumps in order, restart the main engine, inform the bridge and investigate the cause.
• Q: Why is the bell book important? A: It is the contemporaneous legal record of every bridge telegraph order and the engine's response, used as evidence in collision, grounding and casualty investigations.
• Q: What rest hours must a watchkeeper get? A: Under STCW and MLC 2006, a minimum of 10 hours in any 24-hour period and 77 hours in any 7 days, in no more than two periods with one of at least 6 hours; records are kept and inspected.
• Q: You smell burning oil but all alarms are normal. What do you do? A: Trust the senses over the panel — trace it immediately, checking hot surfaces, fuel pipe leaks and insulation near the exhaust manifold and turbocharger, inform the bridge and Chief Engineer, and keep firefighting means ready; a leak spraying onto a surface above about 220 °C is the classic engine room fire.

Common mistakes

• Listing hourly readings without explaining what the trend means — examiners want the interpretation (which unit, what fault, what action), not a copied log sheet.
• Confusing standing orders (permanent, Chief Engineer) with night orders (specific to one night) and with the bridge's own orders.
• Saying UMS means nobody is responsible — the duty engineer remains responsible at all times and must carry the alarm.
• Forgetting the Oil Record Book entry when describing bilge or sludge operations, or quoting 15 ppm without the "en route and outside special areas" conditions.
• Opening crankcase doors immediately after an oil mist alarm, or opening a scavenge trunk while hot, in a viva answer — both are dangerous and marked wrong.
• Writing that alarms may be isolated "to stop the nuisance"; any override must be authorised, recorded and time-limited, and a taped alarm is a Port State Control detainable item.
• Missing the human element — fitness for duty, rest hours, reporting an unfit reliever, and informing the bridge — which carries as many marks as the machinery detail.

Related topics

Ship construction and stability · Naval architecture basics · Ship safety and fire fighting · Marine diesel engines and propulsion plant · Marine auxiliary machinery and pumps · Marine electrical systems and power management