All you need to know about the Supreme Athmos!

The Supreme Athmos® air-type seal is the seal that guarantees zero emissions of oil, enables Condition Monitoring of the seal and provides a safe operation by preventing water entering into the stern tube or thruster. The Supreme Athmos is suitable for ships with a limited draught (up to five metres). This seal is designed for yachts, inland vessels and ferries. Read all about this VGP-compliant seal!

About the Supreme Athmos

The system is designed for vessels with a low draught, provides zero emission of oil into the marine environment and provides safe operation by preventing water entering your vessel’s system. The standard Supreme Athmos aft seal consists of bronze housing parts, a chrome steel liner, one oil and two water-repellent NBR lip seals. The Athmos system consists of a control unit, containing electronic and mechanical parts as well as a drain tank.

The leakage collected in the seal is transported to a small drain tank by creating an air flow. Once this tank is filled, it will be automatically emptied in the general dirty oil tank of the vessel.

A display on the control unit shows the system status and provides information on alarms and leakage rate. This information provides the means for Condition Monitoring of the sealing system. The system is ‘plug and play’; it is possible to adjust the initial system values.

Figure 2: Cross-section Supreme Athmos


  • The Supreme Athmos has an air and drain system that prevents oil leakage to the environment or water leakage into the stern tube or thruster.
  • The Athmos system includes a drain tank which will be emptied automatically into the vessel’s general waste or dirty oil tank.
  • A display shows the condition of the aft seal.
  • DNV GL has verified this seal and it is in compliance with EPA’s VGP requirements.

Figure 1: Supreme Athmos


  • Zero-emissions of oil
  • Zero-leakage of water into the seal
  • 24/7 Condition Monitoring of the seal
  • Fail-safe modus in case system black-out
  • Compact, self-regulatory system
  • Approved by DNV GL to be in line with the VGP regulations

How does it work?

An air inlet pipe and a drain pipe is connected to the aft seal. The other ends of both pipes are connected to the control unit. The pressure inside the aft seal, between the oil and water- repellent lip seals, stays atmospheric.

The control unit creates an air flow through the aft seal. In case there’s any leakage in the seal an under pressure in the drain pipe transports the content to the drain tank. The working principle can be compared with drinking through a straw. You’re able to drink your beverage with a straw by creating an under pressure in the straw when sucking it.

A blockage of the air inlet pipe or drain pipe is automatically detected and an alarm signal is given. The system’s original settings can be adjusted to adapt to harsher operating conditions of the vessel by changing the frequency and duration of the vacuum time. Because the Athmos system works at intervals, the system has a very low air consumption.

Video Supreme Athmos


Certified by DNV-GL to be in line with VGP regulations


A wide set of options is available to enhance the seal design. The available options include: wear resistant HML liner coating, FKM lip seal compound, dirt barriers and wire winders.

Would you like to know more about a particular topic?

Would you like more information about a particular topic or do you have a good idea for a blog? Let us know! We are happy to share information which you are interested in!

Interested in more information?

Contact Bart van Lee to see how we can help you!

About the author

Ing. Pepijn Swarte

Pepijn studied industrial design engineering at the Delft University of Technology and at The Hague University of Applied Sciences. He has been working for Lagersmit since 2013 and as Product Manager he is responsible for the research and development activities of the Supreme seals.