Caisson Worker

Hyperbaric Medicine


Hyperbaric Shuttle
at Westerschelde


Hyperbaric Shuttle Saint-Petersburg Metro






Caisson workers are also called Compressed Air Workers.  Most of their interventions are inspection of Nuclear Power Plants (for 10 years pressure/leak tests), digging tunnels under pressure or inspection & repair under pressure the TBM cutter heads, and standard caisson works.

The concept of compressed air work must be extended to compressed gas works since mix gases breathing mixtures have been used in tunnelling operations.

HYPERBARIE Sarl can take care of :

  • Design, construction follow up, commissioning of compressed air work plant and equipment, either for the account of the final user, either for the TBM manufacturer, frequently in close cooperation with both.
  • Writing operation procedures and safety manuals and obtaining approval by local authorities when required. 
  • Training all personnel  involved (Site director, Hyperbaric operation superintendents, Lock operators, compressed air workers (French Certificate Hyperbariste Mention D Classe I, II - approval by the French Ministry of Labor), Welders and arc-air operators under pressure.
  • Safety follow up of operations throughout the works and adapt organization to unexpected situations (Polluted area, heavy duty repairs under pressure, changes in procedures (oxygen decompression) eventually change the air lock system for a new one...!

References :

Since 1986, JCLP HYPERBARIE had been involved with more than 75 construction sites with operations in compressed air, for all French contractors who have built tunnels with compressed air, and with most of European and North American TBM manufacturers.
  - Metros : Lille (4 sites), Météor, Eole, Rennes, Cairo (2 sites), Lisbon (3 sites), Madrid, Copenhagen, Strasbourg, Rouen, Sydney, Lyon, St Petersburg...
  - Road Tunnels :  Théo (Lyon), Westerschelde (The Netherlands), El Ahzar (Cairo), Socatop (Paris),
  - Train Tunnels : Villejust, TransChannel, KCRC 320 in Hong-Kong, Groene Hart TGV tunnel in the Netherlands, HK 201. 
  -  Sewage : Many sites in Paris area, Toulouse, Bordeaux, Lyon, Swansea...
  - Technical Tunnels : Berlin (3 sites), Paris...
  - Nuclear Power Plants : Writing the safety specifications for hyperbaric inspections of Nuclear reactor buildings (National French Electricity Board - EDF).

The range of pressures are from 0.6 bar to 6.9 bar(g). The more frequent pressure range is between 1.8 to 3 bar. 
Between 4.5 and 6.9 bar, helium containing breathing mixtures and saturation procedures have been specially developed and used at Westerschelde Tunnels in The Netherlands June/September 2000 - refer to publication,  and for the Metro of Saint Petersburg in 2002/2003 - (for 6 bar). 

Special situation : Digging under compressed air in kerosene contaminated soil (refer to publication)