Environmentally Acceptable Lubricants (EAL) to Meet the Vessel General Permit (VGP) – A Complete Guide.



The Buzzword which caught everyone’s attention in early 2015, was the “ECA – The Emission Control Area”.  This effectiveness made the vessels comply with emission regulations by mandating them to use the 0.1% sulphur fuels or exhaust cleaning systems.

This later part of 2015 could be the EALs to comply with the VGP.

In March 2013, the US Environmental Protection Agency (EPA) published the final version of its 2013 Vessel General Permit (VGP) which will apply to all vessels entering US waters from 19th December 2013.  The VGP requires that “All vessels must use an Environmentally Acceptable Lubricants (EAL) in all oil-to-sea interfaces, unless technically infeasible”.

The applications covered by the VGP, which will be regulated by the US Coast Guard, include

  1. Controllable Pitch Propellers;
  2. Thruster Hydraulic Fluids and
  3. other Oil-to-Sea Interfaces including –
    1. Lubrication Discharges from Paddle Wheel Propulsion; –
    2. Stern Tubes,
    3. Thruster Bearings,
    4. Stabilisers,
    5. Rudder Bearings,
    6. Azimuth Thrusters,
    7. Propulsion Pod Lubrication,
    8. Wire Rope and Mechanical Equipment Subject to Immersion.

Wondering what could be EALs and VGP?

This write up is to throw light on EALs (Environmentally Acceptable Lubricants) and the VGP (Vessel General Permit).  In the U.S. waters, it is to be noted that there are mandatory controls over the discharges from all oil-to-water interfaces.  The ship as well as the shore staffs need to be aware of the same if the vessel need to comply with the law and regulations.

It is essential that a vessel must use Environmentally Acceptable Lubricants (EALs) on any equipment that could possibly release oil into the sea.  It is to be noted that not all EALs comply with VGP and choosing the right lubricant is not that easy.

Now, as a Vessel Manager or a Technical Superintendent, you would be wondering or at least you do not have enough time to think to understand these increasingly upcoming new terminologies (though they are old).

We will elaborate in simple terms:

  1. What is the VGP?
  2. What are EALs?
  3. What are the EAL Criteria?
  4. The Best Choice of Lubricant and How to choose it

It is to be worthy to note that “not all EALs are created equal – those based on synthetic esters offer significant advantages over other common base stocks”.

What is The Vessel General Permit:

The US Environmental Protection Agency (EPA) regulates discharges related to the normal operation of commercial vessels through its Vessel General Permit (VGP).

This permit applies to vessels

  1. Operating inside U.S. waters: within three nautical miles of the U.S. coast and also the Great Lakes.
  2. Currently it applies to vessels greater than 79 feet in length, with some exceptions including armed forces vessels.

The latest amendments to the VGP stipulate the use of EALs in all oil-to-sea interfaces: equipment where seals or surfaces have the potential to release oil into the sea.

Two Important Equipment which falls under these criteria are:

  1. Stern Tube, and
  2. Bow and Stern Thrusters.

The EPA also strongly encourages the use of EALs in above-deck equipment as well. Now let’s move on to the EALs.

What is an EAL?

EALs are defined in the VGP as lubricants that are biodegradable, minimally toxic and are not bioaccumulative.  Furthermore, for the purposes of the VGP, each component of the lubricant formulation that is not biodegradable has to undergo one of a range of tests to confirm that it is not bioaccumulative.  Tests include checking a component’s molecular mass and diameter as well as its solubility in the marine environment.

As said earlier, not all EALs are in compliance with the VGP.  We are sure that your next question would be –

“What Criterias that an EAL should posses to meet the VGP Standards?”

To meet the VGP standard an oil must possess three characteristics.

Biodegradable: A minimum of 60 percent biodegradation within 28 days for 90 percent of the lubricant formulation or 75 percent of the grease formulation.  The finished lubricant may contain up to 10 percent of components not meeting the 60 percent threshold of biodegradability and up to 5 percent of non-biodegradable (but not bio-accumulative) components.  For grease, 25 percent may be either inherently or non-biodegradable (but not bio-accumulative).

Minimally toxic: The finished product must pass acute or chronic toxicity tests or, as an alternative, an evaluation may be conducted on a constituent basis where the ‘lethal concentration’ or the ‘no observed effect concentration’ is measured.

Non-bioaccumulative:  Bioaccumulation occurs when an organism absorbs a toxic substance at a rate greater than the speed at which the substance is lost.  Consequently, to qualify as non-bioaccumulative a substance must not be able to build up to toxic levels.

Types of EALs:

There are three common EAL based stock categories:

  1. Polyglycols
  2. Vegetable oils
  3. Synthetic esters

Depending on the composition,

  • Poly Alkylene glycol (PAG) based EALs offer a range of benefits including
    1. Excellent lubricity,
    2. good load-bearing characteristics,
    3. low temperature properties,
    4. high flash points and
    5. good biodegradability.

They are, however, highly incompatible, making changeovers very costly.

  • Naturally derived vegetable-based lubricants are
    1. Readily biodegradable,
    2. Offer excellent lubricity but are water sensitive,
    3. They also have poor resistance to temperature extremes.


So Which Type of EALs is the Best?

The most effective EALs are based on synthetic esters.

They have

  1. Excellent Operational Capability across a wide range of temperatures,
  2. Possess good lubricity,
  3. Provide excellent corrosion protection,
  4. Excellent biodegradability,  
  5. Exceptional protection from water contamination,
  6. Proven performance,
  7. Outstanding lubricant life, and
  8. Compatibility with mineral oils, making changeovers straightforward.

Conversion from existing mineral oil products to EALs will require time in dry dock for some applications.  It is therefore essential that the changeover process is as easy to manage as possible.  Vessel operators will want to avoid the need for solvent flushing, as required for polyglycols, while also ensuring that their EAL is up to the job.

The optimal solution is therefore an EAL based on synthetic esters as this will ensure total compliance with EPA regulations; provide minimal downtime and offer the best overall protection.

Here is what Lloyd’s Register has to say on EALs – a LR Webinar!

Reference: EPA, LR Guidelines.