Critical to the functional integrity and durability of your product in harsh, hazardous or pressurized environments: the ingress protection (IP) sealing and hermeticity for maximum reliability and minimum risk

Sealing is a complex science, involving physical aspects such as mechanical design, materials and surface science.

Conducting product tests according to the strictest standards, we guide and assist you in the careful selection of solutions with the appropriate level of environmental and hermetic sealing to match the specific influences and conditions in which your device will operate.


There are three main application types requiring sealing:


  • Environmental sealing for equipment used outdoors and exposed to water, rain, sand, dirt, dust or other aggressors for a limited time and limited pressure
  • Hermetic sealing for gas tightness, vacuum applications and  pressurized vessels or equipment used underwater, exposed for a longer time, or used in instrumentation applications requiring a high level of sealing to prevent gas leaks over longer periods of time
  • High pressure sealing for applications exposed to high pressure for extended periods, such as unmanned underwater vehicles or oil & gas systems which must also resist shock and vibration, and whose sealing needs must be combined with high-strength mechanical design to guarantee safe and efficient operations


Our design engineers and manufacturing operators use the highest quality designs, sealing techniques and sealant materials to manufacture our products. For example, our circular panel-mounted and cable-mounted connectors achieve ingress protection up to IP68/IP69 levels or are hermetically sealed down to 10-8 mbar l/s – in both mated and unmated states.

Our solutions

What we mean when we say ‘our solutions are sealed’

Sterilization proof

Gas tight


Sterilization proof

‘Sterile’ or ‘aseptic’ connectors must be sealed to allow devices undergoing sterilization processes to protect their electrical functions from pressurized steam, radiation, and chemicals.


The highly pressurized steam of autoclaves delivers the heat able to kill microorganisms during cycles that usually last 30 minutes. 

Connectors and cable assemblies must be appropriately sealed to withstand repeatedly, during multiple sterilization cycles, ingress from steam saturated with water under at least 15 psi of pressure. To keep their electrical functions safe when going through this high-temperature sterilization method used mostly in hospital settings, medical devices and equipment must use connectors and cables that are also rugged enough to resist hot temperatures.

Gas tight

Hermeticity is one of the toughest challenges you will face when specifying connectors. It is a high level of sealing that prevents gas leaks over longer periods of time.


Hermetic connectivity solutions must be built with specific considerations in mind:

  • The total pressure differential that exists on the device as a whole
  • The vacuum level needed for the application
  • The type of O-ring material to prevent any diffusion effect
  • The connector design and materials (insulating plastics, sealing resins and elastomeric seals) minimizing virtual leak and outgassing effects
  • The installation of the panel-mounted connector with correct seal designs – surface flatness, circular machining grooves for O-ring seal, cleaned panel cut-out’s edges and burrs

Our gas-proof connectors are tested with a leak testing instrument to ensure a leak smaller than 10-8 mbar l/s per IEC 60068-2-17.


Our bulkhead feedthrough connectors are also hermetic. Their body styles are specially designed to allow the passing of electrical signals and power through a panel via two cabled plugs.

Underwater and pressure resistant

To withstand exposure for extended periods of time in liquids under high pressure, applications such as deep-submarine applications or pipeline inspection equipment and seismic evaluation and drilling instrument in oil & gas, require connectors with special designs combining hermetic sealing with high-strength mechanical designs to guarantee safe and efficient operations.


Design engineers face special technical challenges for their marine and underwater applications such as autonomous and remotely operated underwater vehicles (ROV, AUV or UUV), which operate at depths where diving by humans is either impractical or dangerous.


Such demanding applications involved in immersion over long periods require ultra-sealed watertight cabled connectors that achieve an IP68 or IP69 rating in both mated and unmated states.

Salt strongly increases water conductivity, so seawater and salt mist can act as an electrolyte, causing galvanic corrosion. Our IP68/IP69-sealed and hermetic solutions are available with a wide choice of materials and coatings to ensure their resistance to corrosion, while being lightweight and compact.


Hermetically sealed connectivity solutions must be specified with the vacuum level needed for the application, the type of O-ring material, and most importantly, the total pressure differential that exists on the device as a whole.


For the highest reliability of the long-term sealing and installation of cable-mounted connectors in such demanding applications, we recommend overmolding the plug’s back-end. This offers a strong hermetic link between cable and connector even in applications subjected to intense mechanical load.

Ingress protection (IP)

The Ingress Protection (IP) classification system provides a method described in IEC 60529 for defining the sealing level of various electronic solutions and connector products. While the first number describes the level of protection from solid objects, the second one relates to protection from liquids. The digits indicate conformity with the conditions summarized in the table below.

Multiple seals

The most rugged connectors have barriers in multiple places, protecting against dirt, dust, water and gas from various angles and intensities, with clearly independent sealing functions designed to control the connector’s performance for every requirement.

Illustration (left): Sealing locations that help create an IP68 rating in plugs and receptacles in the Fischer Core Series line: a) interface seal, b) panel seal, c) sealing of block, d) cable seal.

Immersion test

IP68 sealed at 2 bars during 24 hours


To test the IP68 sealing performance of the Fischer Freedom™ Series, the connectors are immersed at 2 bars (equivalent to 20 m) for 24 hours.


The immersion test can be rated IP68 and is compliant with the Military Standard 810 Method 512.6 and Procedure I.

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