- Allied Colloids
- Amec
- Amersham International
- Anglian Water
- Associated Octel
- Astrazeneca
- Baker Process
- Bayer
- Bechtel
- Biwater Europe
- BP Chemicals
- BP Oil
- Boc
- British Gas
- Bush Boake Allen
- Chevron Oil
- Chiltern Water
- Cleanaway
- Croda Resin
- Crown House
- Cyanamid
- Dow Corning
- ECC
- Exxonmobil Chemical
- Foster Wheeler Energy
- Glaxosmithkline
- Great Lakes UK
- Halliburton B & R
- Holliday Dyes and Chemicals
- Hyrolec Technical Services
- Intec Aea Technology
- Jacobs International
- John Crane
- Kennicott Water Systems
- Kodak
- Kvaerner Process
- Laporte Fine Chemicals
- Lever Brothers
- Linde Cryogenics
- Linde Gas
- Liquid Gas Equipment
- Millenium Inorganic Chemicals
- Mitchell Cotts Chemicals
- National Power
- Nestles
- Norsk Hydro
- Novartis
- Pakistan Petroleum
- Pall Europe
- PCI Membrane Systems
- Phillips Petroleum
- Proctor & Gamble
- Resinous Chemicals
- Rhodia
- Roche Products
- Salt Union
- SCM Chemicals
- Severn Trent Water
- Siemens
- Shell
- Statoil
- Sterling Organics
- Sulzer UK
- Sygenta
- Texaco
- Thames Water
- Tioxide
- Total Oil
- Toyota
- Vivendi Dewplan
- Warwick International
- Welsh Water
- Yorkshire Chemicals

