Thermal vacuum testing
15 Jun 2022



​From telecommunication satellites to components, our vacuum test chambers can replicate a variety of space environments to meet your test requirements.

Door to the ​7m vacuum chamber in the National Satellite Test Facility

​​​​​​​​​​​​7m Vacuum C​hamber in the National Satellite Test Facility

Credit: STFC RAL Space

RAL Space has 11 vacuum test chambers ranging from less than half a meter to 7 meters in diameter, designed to simulate the vacuum and thermal conditions in space.​​

Learn more about which scale of facility i​s right for you below:

Small-scal​e – thermal f​acilities

​For smaller payloads, a wide range of other thermal vacuum chambers are also available within RAL Space.

Each of the Space Test Chambers (STC) Suites has a similar layout, it consists of a vacuum chamber with doors either end that open into cleanrooms. At the side of the chamber, linking the two cleanrooms is an additional cleanroom that provides access to the chamber feedthrough ports.

Up to 1m diameter thermal vacuum chambers

    3 smaller vacuum chambers
  • Clean rooms standard of class 6 (1,000)
  • No overhead cranes
  • Access doors – size 2.0 m wide x 2.4 ​m high​

Small thermal vacuum chambers

  • Three chamber suites, each accommodating multiple chambers
  • Overall size range 0.5 m diameter to 1 m diameter
  • Temperature range -180°C to +150°C
  • Base pressure <1E-5 mbar​
  • Dedicated provision for EGSE


Space Test Chamber 13 meter vacuum chamber

  • 2.6m diameter, 5.4m long usable space, with vibration isolation
  • Temperature range -196°C to +150°C
  • Base pressure <1E-5 mbar
  • Dedicated OGSE rooms 
  • Direct EGSE access areas 
  • Dry pumping system throughout
  • Chambers open into cleanrooms for contamination control


​​Large-scale –​ thermal facilities

Space Test Chambers 2 and 3

5 m vacuum chamber

Designed for optical calibration campaigns, these two space test chamber suites are suitable for testing of small to medium sized spacecraft, or large instrument payloads.

Each chamber is arranged over a dedicated seismic block, allowing the space hardware inside to be de-coupled from the building, providing a quiet environment for precise instrument calibration. In addition, each chamber suite has a clean room in front of the chamber, an optically dark clean room to the rear of the chamber and an EGSE space to the side. 

Customers using these chambers will also benefit from access to a dedicated customer office for the duration of the test campaign.

  • ​4.7m diameter, 6m long usable space in ISO 6 class clean room (with a smaller area at class 5) with vibration isolation for independent mounting rails within the chamber.
  • Clean room crane capacity: 5 tonnes, clean room crane height: 9 meters
  • Access door to the clean room: 6m wide x 6.1m high
  • 46 thermal zones, allowing 90 K to 393 K at 1 K/min
  • Base pressure <1E-5 mbar with a fully secondary pumping
  • Payload DAS channels: 500 x T-type TC
  • Dedicated Optical Ground Support Equipment (OGSE) room
  • Dedicated EGSE room with access from clean room or corridor
  • 40 DC power supply (0-32 V & 0-5 A)
  • RGA and TQCM available​

7 meter vacuum chamber in the National Satellite Test ChamberLarge Space Test Chamber

A bespoke thermal vacuum chamber consists of a large cylindrical vacuum vessel lined with temperature-controlled panels.

From telecommunication satellites to interplanetary landers, the Large Space Test Chamber (LSTC) can replicate a variety of space environments to meet your test requirements.

  • Dedicated operational team
  • 7 m diameter, 12m long usable space in ISO 8 class clean room
  • 10 thermal zones, allowing 95 K to 400 K at 1 K/min
  • Base pressure <1E-5 mbar with a fully redundant primary and secondary pumping
  • Payload DAS channels: 900 x T-type TC, 96 x 4-wire PT100, 48 x 0-60V, 48 x 0-20mA
  • Preparation and Electrical Ground Support Equipment (EGSE) space available together with UPS/ generator
  • MGSE to rotate the satellite from vertical to horizontal for loading into the chamber
  • Access platform (if needed) around the satellite compatible with vacuum
  • 120 DC power supply (0-60 V & 0-10 A)
  • RGA and TQCM available

 Located in the National Satellite Test Facility, the LSTC is available alongside a complete suite of large-scale testing capabilities. For further information, please read the NSTF frequently asked question page. ​​

​Dimensions​ of the thermal facilities available at RAL Space

11 vacuum chambers available at RAL Space arranged in size order

ChamberWorking DiameterWorking LengthWorking Volume
10.6 m0.8 m0.2 m3 
21.0 m1.7 m1.3 m3
41.1 m1.5 m1.3 m3
51.1 m2.1 m1.9 m3 
60.9 m
0.4 m0.3 m3 
71.5 m1.3 m2.1 m3 
80.4 m0.4 m 
0.1 m3 
Space Test Chamber 1
2.7 m5.5 m30.6 m3 
Space Test Chamber 2 & 34.7 m6.0 m104.0 m3 
Large Space Test Chamber
7.0 m
12.0 m 
416.8 m3

How to access our facilities

As the UK's national space laboratory, we occupy a unique and independent position between industry, academia and government. Our facilities are open to everyone on a commercial basis, whether based in the UK or internationally.

To enquire about use of our test facilities please:



Image 1 - ​Smaller vacuum chambers. Credit: STFC RAL Space​​ 

Image 2 - 3 m vacuum chamber. Credit: STFC RAL Space​

Image 3 - 5 m vacuum chamber. Credit: STFC RAL Space

Image 4 - 7 m vacuum chamber in the National Satellite Test Facility. Credit: STFC RAL Space

Image 5 - Suite of 11 vacuum chambers in RAL Space. Credit: STFC RAL Space