Revised Marine Order 504


A new version of Marine Order 504 is now in effect.

What is minimum crewing?

Minimum crewing is the minimum number of crew, including the master, applicable to a vessel based on length using the following table:

VesselTotal minimum figure for master and crew (including engineer)MasterEngineer
≥55 m and <80 m#    411
≥35 m and <55 m#311
≥12 m and <35 m#2*11
<12 m1**1

#Provided the vessel is <3000 GT and <3000 kW.

*In the case of a vessel ≤750 kW propulsion power, the master and engineer roles may be combined in the one person if the master holds a certificate which permits the holder to operate the engines of the vessel. In that case, there must still be another crew member on board to make up the total of 2. In the case of a vessel >750 kW propulsion power, the master and engineer roles cannot be combined in the one person.

**If the master of the vessel does not hold a certificate which permits the holder to operate the engines of the vessel, there must be an additional crew member on board who holds an engineering certificate.


Do you have enough crew?

Know your vessel’s crewing requirements.

On 1 August 2023, the minimum crewing table has been simplified and requirements for rest on domestic commercial vessels has been strengthened.

fully crewed
How do I manage rest? 

When operating under minimum crewing, the vessel owner must ensure that the master and each crew member gets 10 hours rest in every 24-hour period.

The 10 hours do not need to be continuous, however you must ensure that the person has sufficient periods of rest to allow them to recharge before recommencing work. 

For the purposes of minimum crewing ‘rest’ means a period of time when a person is free from all duties and functions.

This period can only be interrupted in the case of an emergency.

Guidance is available at Managing crew fatigue (

What if I can't provide the master and crew with the required rest?

If you can't provide the master and each crew member with at least 10 hours of rest in every 24-hour period, this means you cannot safely operate the vessel under minimum crewing and you will need to operate with appropriate crewing.

If your appropriate crewing is the same as minimum crewing, you may need to re-assess your appropriate crewing determination.

The appropriate crewing determination must be demonstrated in your safety management system and be made readily available to the master and crew.    
The minimum crewing table is based on the length of the vessel only, it does not consider for example the kinds of operations, operational area and emergency preparedness.

With appropriate crewing the owner must factor these considerations and others, as per Marine Order 504, into their crewing evaluation.


4.6m fishing vessel (Class 3D) with 55kW propulsion power

This vessel operates within sheltered waters limits and no more than 1nm from land at any given time.

The owner/master operates between the hours of 5:00am and 2:00pm when fishing and takes into account the time taken to travel to the boat ramp in the morning, processing fish and travel home at the end of the day.

In total the owner calculates they are working for a maximum period of between 11 and 12 hours per day. Based on this, the owner is satisfied that they have sufficient rest and can safely operate with one Coxswain as per the minimum crewing requirements table.


9.4m line boat (Class 2D) with 261kW propulsion power

This vessel operates within harbour limits (sheltered waters) and is responsible for taking mooring lines from ships to the wharf.

As the port operates 24 hours a day, the vessel and crew can be called upon at any time during their shift. 

Crews operate on 12-hour shifts and the owner has a system in place to ensure they have sufficient crews available to undertake the duties required without breaking the company’s 12-hour shift policy. 

Given the nature of the work and requirements for more than one person to operate the vessel, the owner has determined that the vessel cannot operate under minimum manning.

The owner has undertaken an appropriate crewing determination.


23.8m prawn trawler (Class 3B) with 336kW propulsion power

This vessel operates at sea for weeks at a time during the prawning season, only returning to port to offload catch and for re-supply as required.

Because of the distances the vessel needs to travel to and from the fishing grounds, the requirements for sufficient crew to undertake fishing operations and working at night, the owner has determined that they cannot safely operate under the minimum crewing arrangements.

The owner therefore undertakes an appropriate crewing determination.


82m powered barge (Class 2B) with 895kW propulsion power

As this vessel is ≥80m in length the owner cannot rely upon the minimum crewing table.

The owner will need to apply to AMSA for approval of their appropriate crewing determination.

This would also be required, irrespective of vessel length, if the vessel had either propulsion power ≥3000kW or gross tonnage ≥3000GT.

Example scenarios of minimum crewing requirements