Offshore Vacuum Units for Hazardous Areas

Calder offshore vacuum units operate in hazardous environments. They are designed accordance with the hazardous area standards hazardous area standards of the region such as ATEX, NORSOK, or IECEx. These offshore vacuum units utilise positive displacement or liquid ring technologies to provide vacuum performance with pressures up to 810 mbar and flows up to 50m³/min.

MultiVac units are used by customers for a variety of vacuum applications including: waste transfer, chemical/liquid recovery, bulk powder removal, ventilation, pigging, descaling and de-sanding operations.

The MultiVac can be diesel engine or electric motor driven, and there is a range of pressures, flows, and control options. Whether crash frame mounted for weight minimization, or container mounted for maximum protection and noise attenuation, our range of standard vacuum units and our bespoke design capabilities ensure we can provide the right vacuum unit for your offshore, hazardous area requirements.

Vacuum – diesel

Vacuum – electric

Crash Frame

The offshore-certified crash frame allows a reduced-weight lift and a smaller footprint than the containerised version. It offers basic protection against damage during loading and offloading operations.


The container is certified to ISO 10855-1 and offers maximum protection from the elements and from damage in transit. The container aids noise attenuation with further noise attenuation options available. Controls and services are externally mounted to give easy operator access during set-up and operation.

Offshore Vacuum Units – Quality

The MultiVac unit follows the same principles of quality, reliability, safety, ease of operation and ease of maintenance as our successful range of MultiJet high pressure water jetting machines. With safety paramount and operational uptime critical, we select only the best components and package them in unit designs which are subject to the continual improvement regime that keeps Calder at the forefront of offshore vacuum technology.

To speak directly with one of our sales engineers, call +44 1905 751790 or email

  • Vortex separator for solids removal.
  • Solids tank capacity 1.7 m³.
  • Removal waste tray.
  • Waste tray capacity 1.0 m³.
  • Pump impeller oil dosing system.
  • Electric or pneumatic control system and shutdowns.
  • External access to fuel fill, services manifold, and the control panel.
  • Gas and fire detection.
  • Fire suppression systems.
  • Noise attenuation – Various options to reduce noise levels.
  • High ambient temperature operation for environments up to 50°C.
  • Maintenance lifting points – Located above internal components to enable fitting of chain hoist to assist with equipment removal/maintenance.
  • Internal hazardous area lighting.

Material/waste removal:

  • of coatings from surface preparation.
  • from tanks, vessels, mud pits and silos.
  • from hazardous drainage systems.
  • of viscous, dense materials.
  • from confined spaces.

  • Chemical, fuel, and liquid recovery from open/bunded areas.
  • Transfer of waste from open top skips to closed skips.
  • Bulk powder removal.
  • High flow ventilation of hazardous atmospheres.
  • Hydrocarbon heavy waste removal while atmospheric venting.
  • Pigging support operations – prevention of uncontrolled release of hydrocarbon materials.
  • Descaling support – control of water discharge.
  • Online/offline de-sanding operations.