Operational Guide · Registers & Logbooks

# Integrated Automation Systems and Unmanned Machinery Space (UMS)

The UMS notation does not certify an absence of supervision, but a level of safety equivalent to that of a manned engine room: SOLAS Chapter II-1 Part E sets out the precise conditions for obtaining it.

UMS automation SOLAS II-1 periodically unattended machinery space

## Operational Explanation

The UMS notation (Unmanned/Unattended Machinery Space) attested by the Classification Society allows a ship to operate with the engine room periodically unattended, typically at night, with the Chief Engineer recallable via a dedicated system in the event of an alarm. This is not optional automation: SOLAS Chapter II-1, Regulations 46-54 (Part E) impose a detailed set of technical requirements — from fire prevention to flooding protection, from propulsion system control to alarm systems — the guiding principle of which is that the ship's safety in all navigational conditions must be equivalent to that of a ship with a permanently manned engine room.

The technical core of the system is the Integrated Automation System (IAS): the platform that collects alarms, monitoring and control from machinery, electrical and sometimes cargo systems into a single operator interface, with the engineer's alarm call system audible in the accommodation and operable from the engine control room and the local control station.

## Regulatory Reference

SOLAS Chapter II-1, Regulations 46-54 (Part E): detailed requirements for ships with a periodically unattended machinery space, including fire prevention, flooding protection, propulsion control from the bridge/control room, alarm systems and continuity of electrical power. The Class notation (e.g. UMS, AUT-UMS depending on the Society) attests compliance and is verified at every survey.

## Scope of Application

Every ship operating with a periodically unattended machinery space under the assigned Class notation, with the Chief Engineer responsible for maintaining and periodically verifying the efficiency of the alarm and call systems.

## Procedure / How to Complete It

1. Daily, before leaving the machinery space unattended, verify that all critical alarms are active and functioning (periodic test according to the approved plan).
2. Confirm that the engineer's call system is audible and operative both from the engine control room and from the local control station.
3. Maintain a documented alarm response procedure, with maximum response times defined for returning to the engine room.
4. Periodically test the ability of the Integrated Automation System (IAS) to manage propulsion, power generation and alarms as specified by the approved maintenance plan.
5. Document every malfunction of the automation system and suspend the UMS regime if a critical alarm cannot be verified as functioning.

## Practical Example

Example: before activating the night-time UMS regime, the engineer on watch verifies the test of the general alarm, the fire system and the call system to the Chief Engineer's accommodation, recording the outcome in the engine log book before leaving the machinery space unattended.

## Real Cases

The adoption of periodically unattended machinery spaces is now the norm across most of the modern merchant fleet, but requires a daily verification discipline that is often underestimated: compliance with the UMS notation is not a permanent attribute of the ship, but an operating condition that must be actively confirmed every time before leaving the machinery space unattended.

## Common Mistakes Mistake Library

Mistake | Consequence | How to avoid it
--- | --- | ---
UMS regime kept active despite a critical alarm reported as unverifiable | Loss of the equivalent safety required by SOLAS II-1 Part E without anyone noticing until a real event | Always suspend the UMS regime when a critical alarm cannot be confirmed as functioning
Periodic alarm test treated as a documentary formality rather than a genuine functional check | Malfunction of the call system discovered only during a real emergency | Carry out the test as a genuine functional check, not a simple tick on a form
Alarm response procedure not documented with defined maximum times | Delayed and non-standardized response in the event of a night-time alarm | Always document a response procedure with maximum times for returning to the engine room

## PSC Observations

PSCOs may verify the validity of the UMS/AUT-UMS notation on the Class certificates and request practical demonstration of the alarm and call system's operation during the inspection.

## Operational Tips

- Never treat the UMS notation as a permanent attribute of the ship: it must be actively confirmed every time before leaving the machinery space unattended.
- Always verify that the call system is audible both in the engine control room and in the local control station, not just one of the two.
- Document every malfunction of the automation system, even minor ones: a pattern of small malfunctions often anticipates a more serious failure.

## Checklist

- Critical alarms verified as active and functioning before leaving the machinery space unattended
- Engineer's call system verified as audible from the engine control room and the local control station
- Alarm response procedure documented with defined maximum times
- Periodic test of the Integrated Automation System (IAS) carried out according to the approved plan
- UMS regime suspended in the event of a critical alarm not verifiable as functioning

## FAQ

What exactly does the UMS notation mean?
It attests that the ship can operate with the machinery space periodically unattended while maintaining a level of safety equivalent to that of a permanently manned engine room, under the detailed requirements of SOLAS Chapter II-1 Part E.
Who recalls the engineer in the event of an alarm during the UMS regime?
A dedicated call system (engineer's alarm), audible in the engineers' accommodation and operable both from the engine control room and the local control station.
What is the Integrated Automation System (IAS)?
The platform that collects alarms, monitoring and control of machinery and electrical systems into a single operator interface, the technical basis for the periodically unattended machinery space regime.
🎬 Additional photos, videos and interactive diagrams for this topic will be available in a future version of the platform.

## Related Topics

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