- ABB Ltd. - Bangalore
- Allen Bradly India Ltd. - U. P.
- Andrew Yule & Co. Ltd. - Calcutta
- APSEB; Nellore, T.P.S.
- Associated Cement Co. Ltd. - Thane
- Alstom India Ltd. - Calcutta
- Bridge & Roof Co. (India) Ltd. - Calcutta
- Bharat Heavy Electricals Ltd. - Delhi + Bangalore
- British Oxygen Limited. - Calcutta
- Century Pulp & Paper Limited. - Calcutta
- Calcutta Electric Supply Corporation Ltd. - Calcutta
- Crompton Greaves Ltd. - Calcutta
- CMC Limited. - Calcutta
- DC Industrial plant Services Ltd. - Calcutta
- Damodar Valley Corporation
- Elecon Engg. Co. Ltd. - Gujrat
- Emami Cement
- Geo Miller (India) Ltd. - New Delhi
- GNDTPS - Punjab State Electricity Board.
- GE Power
- Himenviro Engineering Co.
- Hindusthan Lever Limited. - Haldia
- Ingersollrand (I) Ltd. - Calcutta
- ION Exchange Limited. - Calcutta & Pune
- I.F.B. Agro Industries Ltd. - Calcutta
- IFFCO Paradeep
- Jaypee Cement
- JSPL
- K G Khosla Compressors Ltd. - Pune
- Larsen & Toubro Ltd. - Kolkata.
- McNally Bharat
- Macawber Beekay
- Nagpur Alloy Castings Ltd. : Steel Plant Division - M.P.
- NICCO Corporation Ltd.
- NTPC Ltd.
- NGSL
- Orissa Sponge Iron Ltd. - Keonjhar, Orissa
- OTTO India Ltd. - Calcutta
- Porel Dass Water & Effluent Control Pvt. Ltd.
- Reliance Cement
- SAIL
- Sainik Mining And Allied Services Ltd.
- SMS India Ltd. - Calcutta
- Tata Steel Ltd. - Jamshedpur and Kalinganagar
- Telecom Department - Calcutta
- TRF Limited. - Jamshedpur
- Tinplate Co. of India Ltd. - Jamshedpur
- Tata Ryer Son India Ltd. - Calcutta
- UCC (I) Limited - Calcutta
- Voltas Limited - Kolkata
- WBPDCL
- WPIL