Unmanned machinery space (UMS) – Machinery spaces that are controlled from the bridge rather than from a control room located within the engine room compartment commonly known as ECR

All machinery spaces of category A and all other spaces containing propulsion machinery, boilers, oil fuel units, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing, ventilation and air conditioning machinery and trunk to such spaces, (SOLAS).

UMS or Unattended Machinery Spaces is a marine automation system for ship’s engine room. Unlike conventional watch system on normal cargo ships, in UMS class vessels, there are usually no engineer officers on watch in the engine room (from 1700 hrs. to 0600 hrs). If there is a malfunction in any machinery, an alarm will be sounded in the engine room as well as in the ‘on duty’ engineer’s cabin. It’s then the engineer’s duty to go down in the engine room and investigate the alarm.

But Do all ships have UMS – Unattended Machinery Spaces? Alsolutely No

Merchant Navy Ships are classified as Manned Ships or UMS (Unattended Machinery Spaces) Ships depending on the watch keeping system followed in the Engine Room of that particular ship.

There are two kind of Ship types

1. UMS Ships (Unattended Machinery Spaces)
2. Manned Ships

What are Manned Ships? Manned ships are those ships where engine room follows the same watch keeping system as that of the Bridge watch keeping. In manned engine room ships the 2nd engineer keeps the 4 to 8 watch in the morning & evening, 3rd engineer keeps the 12 to 4 watch in the afternoon & midnight and 4th engineer keeps the 8 to 12 watch in the morning and night time. The engineers are accompanied by their respective duty oilers. The Chief Engineer, Electro Technical Officer (ETO), Fitter and Junior engineer work in day work and always available on call during night time.

In UMS (Unattended Machinery Spaces) Ship all the crew in the engine room works in day work that is from morning 8 to evening 6. The duty engineer and duty oiler, in addition to day work, go for UMS safety rounds in the morning 7 to 8 and night time 11 to 12. Please note that the day work hours may differ from ship to ship depending on the Voyage type, Port calls and Machinery breakdowns.

After 6 o’clock in the evening, the engine room goes into the UMS mode until next day morning 7 o’clock. The 2nd engineer, 3rd engineer & 4th engineer will take the UMS duties in rotation.

How UMS works ? Functioning of UMS explained

The duty engineers have a UMS alarm panel in their cabin. The UMS panel is also present in the chief engineer’s cabin, navigation bridge and all other common spaces like officers mess room, duty mess room, officers recreation room and gymnasium.

Whenever there is something wrong with any machinery in the engine room during UMS period, the UMS alarm sounds in the duty engineers cabin, on the bridge and in the common spaces.

The duty engineer can check the alarm details in his cabin panel itself then he accepts the alarm in his cabin and goes down in the engine room and accepts the alarm. This process of accepting the alarm should be carried out within 5 minutes otherwise the engineer’s call will get activated and the alarm will sound in each duty engineer’s cabin and chief engineer’s cabin.

When the UMS alarm gets activated, the dead man system also gets activated with it automatically. The duty engineer should rectify the problem and should reset the alarm. He can call for help if required. The duty engineer needs to put off the DEAD MAN ALARM manually before going out of the engine room.

What is Dead Man alarm System :

The dead man alarm is a safety measure. Whenever there is a alarm during the UMS time the duty engineer is the only person goes down in the engine room to rectify the alarm and his safety is paramount. That is why dead man alarm gets activated automatically together with UMS alarm. While the duty engineer is working down in the engine room, he needs to reset the UMS alarm every 20 minutes which van be done from every platform in the engine room.

If the duty engineer fails to reset the dead man alarm during these 20 minutes, there will be a warning light indication for the next 3 minutes. The duty engineer can also reset the alarm during these 3 minutes time. But if he fails to reset the dead man alarm during the warning time also then the dead man alarm sounds in the engine room, navigation bridge and also in the accommodation.

And the rest of the crew will come to know that something wrong has happened with the duty engineer and he needs immediate help. This way dead man alarm works for the safety of the duty engineer.

What are the Essential Requirements for Unattended Machinery Space (UMS) Ship?

Essential requirements for any unattended machinery space (UMS) Ship to able to sail at sea are enumerated in the SOLAS 1974 Chapter II-1, regulations 46 to regulation 53. The main points discussed in this chapter are discussed in this article.

Requirements for Unattended Machinery Space (UMS) Ship

1. Fire Prevention & Precaution

• Arrangement should be provided on UMS ship to detect and give alarm in case of fire.
• In the boiler air supply casing and uptake.
• In scavenge space of propulsion machinery.
• In engines of power 2250 Kw and above or cylinders having bore more than 300mm should be provided with oil mist detector for crankcase or bearing temperature monitor or either of two.

2. Protection against Flooding

Bilge well in UMS ship should be located and provided in such a manner that the accumulation of liquid is detected at normal angle of heel and trim and should also have enough space to accommodate the drainage of liquid during unattended period.

In case of automatic starting of bilge pump, the alarm should be provided to indicate that the flow of liquid pumped is more than the capacity of the pump.

3. Control of Propulsion Machinery from Navigation Bridge

The ship should be able to be controlled from bridge under all sailing conditions. The bridge should be able to control the speed, direction of thrust, and should be able to change the pitch in case of controllable pitch propeller.

Emergency stop should be provided on navigating bridge, independent of bridge control system.

The remote operation of the propulsion should be possible from one location at a time; at such connection interconnected control position are permitted.

The number of consecutive automatic attempt which fails to start the propulsion machinery shall be limited to safeguard sufficient starting air pressure.

4. Centralized control & instruments are required in Machinery Space

Centralized control system should be there so that engineers may be called to the machinery space during emergencies from wherever they are.

5. Automatic Fire Detection

Alarms and detection should operate very rapidly and effectively. It should be placed at numerous well sited places for quick response of the detectors.

6. Fire Extinguishing System

There should be arrangement for fire extinguishing system other than the conventional hand extinguishers which can be operated remotely from machinery space. The station must give control of emergency fire pumps, generators, valves, extinguishing media etc.

7. Alarm System

A comprehensive alarm system must be provided for control & accomodation areas.

8. Automatic Start of Emergency Generator

Arrangement for starting of emergency generator and automatic connection to bus bar must be provided in case of blackout condition. Apart from that following points are also to be noted.

1. Local hand control of essential machineries like steering, emergency generator starting, emergency start for main engine etc.
2. Adequate settling tank storage capacity.
3. Regular testing & maintainence of machinery alarms & instruments.

Safety precautions for Unmanned machinery spaces:

1. Personnel should never enter or remain in an unmanned machinery space alone, unless they have received permission from, or been instructed by the engineer officer in charge at the time. They may only be sent to carry out a specific task which they may be expected to complete in a comparatively short time.
2. Before entering the space, at regular intervals whilst in the space and on leaving the space, they must report by telephone, or other means provided, to the duty deck officer. Before they enter the space the method of reporting should be clearly explained. Consideration should be given in appropriate instances to using a `permit-to-work’ .
3. If it is the engineer officer in charge who enters the machinery space alone, he too should report to the deck officer.
4. Notice of safety precautions to be observed by personnel working in unmanned machinery spaces should be clearly displayed at all entrances to the space. Warning should be given that in unmanned machinery spaces there is a likelihood of machinery suddenly starting up.
5. Unmanned machinery spaces should be adequately illuminated at all times.
6. When machinery is under bridge control, the bridge should always be advised when a change in machinery setting is contemplated by the engine room staff, and before a reversion to engine room control of the machinery.

Unmanned machinery space checks

On any ship certified for unmanned operation, the machinery spaces may be unattended for a maximum period of 16 consecutive hours. No vessel is to operate with the machinery spaces unmanned in the following circumstances:

• During preparation for departure .
• During manoeuvring/standby operation.
• At sea or at anchor when the Master or the Chief Engineer requires the Engine Room to be manned due to adverse weather, traffic etc.
• When the cargo handling plant places a high and variable load on the electrical or steam generating plant.
• When port regulations prohibit any unmanned engine room.
• With any fire, major alarm, or safety system inoperative, including any fire detection system zones isolated.
• If any propulsion equipment back up provision is inoperative.
• With any major control or communication system inoperative.
• If the bridge console is inoperative.
• Before the Chief Engineers specific instructions for operating in the unmanned condition have been complied with.

Before Going UMS Checklist – Unmanned Machinery Space

Before going UMS, the Duty Engineer must ensure that all day service tanks for fuel, cylinder oil and header tanks for cooling water, lubricating oil, etc are full. An inspection of all active and operational machinery and systems in all the machinery spaces, particularly for fuel and lubricating oil leakage, is to be carried out.

1. That the main engine is on bridge Control
2. Check that all bilges and seawalls are empty.
3. Test Oil Mist Detector alarm on M.E , test bilge wells High Levels Alarms , test Boiler High/Low/Cut out alarms where applicable
4. Check that bilge pump is in auto position.
5. Check that Emergency DG is in stand-by position.
6. Check that Stand-by DG is on auto-start.
7. Check that steering gear motors are in stand-by position.
8. Check that all stand-by pumps are on auto-start.
9. Check that OWS overboard valve is secured (OWS stopped when E/R unmanned and if not automatic discharge).
10. Check that all fire loops are activated.
11. Check whether all watertight and weather doors/openings are closed.
12. Check that the Purifier Room and Steering Gear door is closed
13. Check cabin / public rooms alarms prior to the engine room being unmanned.
14. Inform bridge and confirm UMS before leaving E/R
15. Check that all flammable liquids are in sealed canisters.
16. Check that all oil spills etc have been cleaned up.
17. Check that all waste, rags and other cleaning materials are stowed away.
18. Check that all Engine Room gear, spare parts etc are properly secured.
19. Check that all alarms are active.
20. Check that all fire detection sensors are active.
21. Check that all fire doors are closed.
22. Test the “Deadman” alarm and Engineer’s Call Alarms, ensuring they are sounding in public rooms, Bridge, Cargo Offices and appropriate cabins.

A Critical Operations Checklist, is to be developed, maintained and used for ensuring all necessary checks are made prior to going unmanned. Once the checklist has been completed, the engine room alarms should be set to “UMS Mode” and the Bridge notified of the engine room status and engineer on duty. An entry should be made in the engine room log book.

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On any ship certified for unmanned operation, the machinery spaces may be unattended for a maximum period of 16 consecutive hours.

No vessel is to operate with the machinery spaces unmanned in the following circumstances:

1. During preparation for departure see section 4 of this chapter.
2. During manoeuvring/standby operation.
3. At sea or at anchor when the Master or the Chief Engineer requires the Engine Room to be manned due to adverse weather, traffic etc.
4. When the cargo handling plant places a high and variable load on the electrical or steam generating plant.
5. When port regulations prohibit any unmanned engine room.
6. With any fire, major alarm, or safety system inoperative, including any fire detection system zones isolated.
7. If any propulsion equipment back up provision is inoperative.
8. With any major control or communication system inoperative.
9. If the bridge console is inoperative.
10. Before the Chief Engineers specific instructions for operating in the unmanned condition have been complied with.

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Rules & Regulations regarding Mandatory IMO Requirements for UMS Ships

Various regulatory authorities at the international level issue rules and regulations for the
installation and operation of control equipment onboard ships. The IMO (International Maritime Organization) has mandatory regulations for ships operating with periodically unattended machinery spaces and these are contained in the International Convention for the Safety of Life At Sea (SOLAS).

Further mandatory regulations may be imposed by the National Administration with which
the ship is registered and these usually take the form of an interpretation of SOLAS regulations.
The international classification societies, such as Lloyd’s Register of Shipping, Det Norske
Veritas, American Bureau of Shipping, Bureau Veritas and Germanischer Lloyd, issue detailed
rules specifying the minimum controls, alarms and safeguards that need to be fitted for the ship
to be assigned a classification notation.

The classification societies meet through the forum of IACS (International Association of Classification Societies) to ensure that there is no significant difference between their minimum requirements and that the SOLAS regulations will also be complied with through the classification process.

Also Read Unmanned Machinery Space (UMS) and its Essential Requirements

It is important to appreciate that when a ship is assigned the UMS notation (or equivalent);
the flag authority will normally permit some dispensation on the engineering manning level.
This dispensation is only permitted while the UMS notation remains valid and accordingly
the classification societies periodically survey the controls, alarms and safety systems through
the ship’s service life.

If defects were found in the control engineering installations, which
affect the UMS notation, it would be suspended. UMS stands for “Unmanned or Unattended Machinery Spaces”; these ships generally have lesser manpower due to sophistication and hence need more stringent methods of ensuring seaworthiness of ships.

Control of Propulsion Equipment from the Bridge

A control system to operate the main machinery must be provided on the bridge. The
bridge watch keeper must have easy access to the emergency control system.

Centralized Control

A centralized control room that is easily accessible is to be provided with the adequate
instrumentation and equipment. The equipment installed therein shall capable of
monitoring and operating all main and auxiliary machinery.

Automatic Fire Detection and Alarm System

A detection and alarm system, which operates very rapidly, should also be capable of
giving an early warning of fire in the machinery spaces especially for the following:

• (a) The Boiler
• (b) The Scavenge air belt of the Main Engine
• (c) The Crankcase of the Main Engine

Note: Oil mist detectors are to be installed for engines of 2250 kW and above, or when the
engine bore exceeds 300mm – especially in hazardous areas. These detectors are
numerous, well sited and respond quickly

Comprehensive Machinery Alarm System

This system should be capable of displaying (by means of a mimic panel) any
abnormality of the machinery, both on the Bridge, as well as in the Accommodation spaces,
including the Duty Engineer’s cabin, the Chief Engineer’s cabin and all public rooms.
The power supply for this alarm system should have a back-up from the emergency
switchboard, in case of a blackout, and there should be an alarm, to indicate this condition.

Fire Control Station

In addition to conventional portable extinguishers, it is mandatory to have a fire station
that is remotely located from the machinery space. The station must facilitate the control
of emergency pumps, generators, valves, ventilators, extinguishing media, etc.

Automatic High Bilge Level Alarms and Pumping Systems

In order to ensure protection against flooding, bilge wells are to be monitored for
excessive levels under normal angles of heel and trim. For auto bilge pumps, a ‘long-run’
alarm should be provided. This indicates excessive filling of the bilge, since the pump is
generally not able to cope with the ingress of water.

The controls for the bilge pump and remote valves should be easily approachable and
above the possible level of flooding. Sensing devices in bilges with alarms and hand or
automatic pump control is provided.

Automatically Started Emergency Generator for Essential Services

This generator is almost always connected to separate emergency bus bars in a
dedicated switchboard, located away from the main generating station. The primary
function of such a generator is to automatically overcome electrical blackout or a dead ship
conditions within (a maximum of) 45 seconds.

Local (Manual) Control of Essential Services

Local controllers operate certain machinery that cannot be controlled automatically or
which is best controlled manually.

Automatic Control System for the Boiler

The boiler system is controlled automatically with the help of a level controller and
amplifier; in addition there is a combustion control system with many safety features
incorporated to prevent fires.

Safety Systems to be installed/fitted onboard ships complying Mandatory IMO Requirements for UMS Ships

1. The arrangements should ensure safety in all conditions, which should be equivalent to running with manned machinery spaces.
2. Adequately designed safety systems are to be provided for the automatic shutdown of the main engine, auxiliary engines or the boiler, in case of any serious malfunction.
3. Auxiliary engines used for power generation must be capable of automatic starting and loading in case of failure of the running machine. This can be done by means of a standby feature.
4. In the case of electrical power systems, means should be provided for shedding excessive load, e.g. a preferential trip, which will shed the load that is considered nonessential for the immediate running of the main engine (e.g. galley power, deck machinery, etc.).
5. All pumps essential for the running of the main engine must be provided in duplicate and an auto stand-by facility shall also be provided. The stand-by pump shall be capable of automatically starting, on detection of failure of the running pump, e.g. by means of a pressure switch. Each pump must be capable of performing the duty independently.
6. Steering gear for U.M.S. operation must be of the type, such that it can automatically isolate and regain steering control, in case of a single failure, by automatic operation of the Isolating valves, e.g., the safe-matic steering system.
7. There should be two separate steering gear pumps, which can independently help to steer the vessel, and one of them must have its power supply through the emergency switchboard, such that it will continue to work, in spite of a blackout, by drawing its power from the emergency supply.
8. There must be an approved system for ensuring safety of the personnel entering the machinery spaces, during U.M.S. operation, for responding to alarms or carrying out essential repairs; for example, there is a dead man alarm system (the alarm operates by means of a timer, which is activated when the duty engineer enters the machinery space.
9. It must be manually reset, after a pre-determined time interval, by means of reset switches located in the engine room. In case of incapacitation of the Duty Engineer, failure to reset the timer will sound the alarm on the Bridge, and someone can be deputed to investigate and take requisite action).

Regular Testing and Maintenance of Instrumentation / Monitoring Systems

There should be periodic inspections or rounds, before and after the unmanning of the
machinery spaces. The modern trend is towards a centralized control room, using a totally integrated system for all aspects of ship operation, including engineering, cargo, navigation and general administration.

In any system, most controlled elements will have one or more of the following points of
operation:

1. Local manual control
2. Remote manual control
3. Automatic control.

Local control implies that the point of control is in the immediate area of the device, whereas
for remote control the point of control is at some distance away from the device, such as in a
control room. The operation of a bilge suction valve in the engine room by its hand wheel is an
example of local manual control.

If the valve was fitted with an extended spindle through to the
deck above and was operated from that point, it would be remote manual control. In both these
cases, a human operator would operate the valve.

If the bilge valve was fitted with a hydraulic motor to operate the valve, and the valve opened
and closed according to the position of a float controller in the bilge well, this would be an
automatic control system. The human element is eliminated in this case.

SOLAS Regulations Related to UMS Marine Control Engineering

Notes: These excerpts of the SOLAS regulations in the previous article (1.7) have been summarized for academic purposes only and are not verbatim. Relevant Classification Societies’ Requirements and other relevant regulations must be referred and adhered to onboard ships in order to ensure compliance.

UMS Requirements for Main Machinery Control

In vessels that have capabilities of remote control of propulsion machinery from the Navigation bridge and the machinery spaces, the speed, direction of thrust and the pitch of the propeller, where applicable, must have means to permit full control from the navigation bridge at all times and under all sailing conditions. In the case of multiple propellers that are designed to operate simultaneously, they may be controlled by one control device.

Remote control must be possible from only one location at a time, with an indicator to show which location is in control. The transfer of control should be in the main machinery control room and is to have means to prevent thrust from changing whilst transferring control from one location to another. Any failure of the remote control station should activate an alarm. A local control mode is also mandatory. The means to permit manual overriding of automatic control should also be provided.

The main propulsion machinery is to have an emergency stopping device on the navigation bridge that is independent of the navigation bridge control system. All orders from the navigation bridge are to be indicated in the main machinery control room or at the maneuvering platform as appropriate. Propeller speed and direction of rotation indicators in the case of fixed pitch propellers or propeller speed and pitch position indicators in the case of controllable pitch propellers are to be provided on the navigation bridge.

Automatic Shutdown

In the event of serious malfunctions in machinery or boiler operations that present any immediate danger, the malfunctioning part of the plant must be automatically shut down while also activating an alarm.

The propulsion system should also be automatically shut down in case of serious damage, complete breakdown or an explosion is imminent. Manual overrides for the main propulsion machinery should only be provided to prevent unintended operation. In such cases, there should be an annunciator to indicate the activation of the manual override.

Special UMS Requirements for Boilers

The quality of the feed water for boilers must be capable of being supervised and controlled. As far as is practicable, the entry of oil or other contaminants, which may adversely affect the boiler should be prevented.

Every boiler that is essential for the safety of the ship must have at least two water level indicators, one of which is to be a gauge glass. Boiler air supply casings, exhausts (uptakes) and scavenging air belts of propulsion machinery are to have early-stage warning devices to detect potential fires and give alarms.

Internal combustion engines of 2,250 kW and above or having cylinders of more than 300 mm bore must be installed with crankcase oil mist detectors or engine bearing temperature monitors or equivalent devices.

UMS Requirements for Alarm Systems

An alarm system to indicate any fault requiring attention must be capable of sounding an audible alarm in the main machinery control room or at the propulsion machinery control position, and indicate visually each separate alarm function at a suitable position.

The alarm system must have a connection to the engineers’ public rooms and to each engineer’s cabin through a selector switch, to ensure connection to at least one of those cabins.

In case any situation arises – that requires action by or the attention of the officer on watch
on the navigation bridge, an audible and visual alarm is to be activated; as far as practicable it
must be fail-safe.

Continuous power supply with means to change-over to a stand-by source, is to be provided for the alarm system. An alarm should be activated if the normal power supply of the alarm system fails.

The alarm system must have features to indicate more than one fault simultaneously and the
acceptance of any alarm should not inhibit another alarm condition.

Accept buttons can be used to turn off the audible warning. However, visual indications of
individual alarms are to remain active until the fault has been rectified.

Water Level Detection in Bulk Carriers

Each cargo hold is to be fitted with water level detectors capable of activating audible and visual alarms for situations when the water level above the inner bottom in any hold reaches a height of 0.5m and also at a height not less than 15% of the depth of cargo hold but not more than 2m. Visual should be capable a clearly and separately indicating both conditions.

In the case of any dry or void space greater than 0.1% of the ship’s maximum displacement volume, that extends forward of the foremost cargo hold (except the chain locker), an alarm should be activated on the navigation bridge if the water level rises 0.1m above the respective deck. Alarm overrides can be used for cargo holds that are used for water ballasting purposes.

Unmanned Machinery Space (UMS) on Ships and its Essential Requirements Pdf Download

Reference: IMO Rules

• What is Deadman Alarm onboard Ships
• Mandatory IMO Requirements for UMS Ships
• Unmanned Machinery Space (UMS) on Ships and its Essential Requirements