HDEO (EP), High Density Environmntal Oil Based Subsea Actuator Fluid Logo
Product Overview

HDEOEP is a High Density Environmental Oil designed for applications where a specific gravity greater than seawater is required. The fluid is designed for use in a wide range of subsea and topside applications where a higher density fluid is desirable.


HDEOEP offers outstanding environmental properties with an OCNS E (with no substitutable components) rating for UK discharge and a Yellow Y1 environmental classification for use in Norwegian waters and meets the toxicity requirements of GOM GMG290000-2012.


HDEOEP exhibits excellent corrosion protection, long term stability, microbiological protection, material compatibility and all round technical performance.


HDEOEP offers outstanding Health and Safety Properties and is classified as 'Non Hazardous' under EU legislation.


HDEOEP has been extensively tested with a wide range of materials commonly used in subsea systems and have been approved with a wide array of equipment manufacturers

Typical Physical Properties
HDEO(EP) Typical Physical Properties Chart

*OEO recommends a minimum operating temperature of –10 °C due to rapid increase in viscosity below -10 °C.

Note these properties are typical for the product but do not constitute a specification.

Key Properties
  • Outstanding Environmental Profile

  • Yellow Y1 / OCNS Class E for Discharge

  • Meets GOM Toxicity Requirements

  • Excellent Health & Safety Properties

  • Excellent Lubrication and Anti-wear

  • Excellent Anti-Corrosion Properties

  • Excellent Microbiological Properties

  • Outstanding Long Term Stability

  • Extensive Material Compatibility Data 

Product Downloads
HDEO(EP) Product Summary
HDEO(EP) Technical Manual
Did You Know...

HDEO (EP) has been used successfully in subsea projects around the globe for many years.


More than 100 projects worldwide use HDEO (EP) and the fluid has been qualified by the vast majority of subsea actuator vendors in the marketplace.

HDEO (EP) is the main industry alternative to ELF/ Total Nemis SN in Subsea Actuators.