CEDIFOP

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venerdì 5 giugno 2015

LIMITATIONS IN THE USE OF SCUBA EQUIPMENT IN OFFSHORE OPERATIONS AND THE ITALIAN SITUATION

by Manos Kouvakis – CEDIFOP Director


SCUBA – Acronym for Self Contained Underwater Breathing Apparatus, was developed in 1942 and, since that time, has been generally used by recreational divers. Its main feature is the supply air from a compressed air tank on the back of the diver, as against surface supply diving, where the gas is supplied to the diver from the surface, through an umbilical. In the past, SCUBA was also often used for commercial purposes, also on request of the clients. Now, after a huge number of accidents and casualties, the limitations of SCUBA, compared to Surface Supplied Diving, have become known. In fact, the use of SCUBA in commercial diving is restricted to Inland/Inshore diving, and always with a safety/communication line to the surface, while “free” SCUBA – i.e. without a safety line - is used only in recreational diving. In July 1994, IMCA in document AODC 065, stated: “SCUBA is a limited technique and it is strongly recommended to NOT use it in any offshore operation, oil and gas installation, construction, civil engineering or savage”. This concept was restated on April 1998, in the document “International Code of Practice for Offshore Diving (IMCA D 014 – Rif.2)” which stated: “SCUBA has many limits and difficulties, because of the limited supply of breathing gas. In no circumstances can the use of SCUBA, instead of a surface supplied system be a solution for safe diving. Moreover, it is stressed that the use of SCUBA is specifically forbidden for offshore operation by several National Regulations. In some case, IMCA Members has been required by potential clients to use SCUBA, because it is thought to be an easy and cheap way to operate, but it should be remembered that it has many serious limitations: for example: 

A Limited gas supply: The time that diver can spend in the water is limited by the by the amount of gas he can carry. This is a problem for divers working underwater as their gas consumption is high In many places of work there are obstacles underwater, which can catch diver. In these cases, SCUBA can represent a serious problem, whereas a diver using Surface Supply would not have a problem as he would have time either to solve it or wait for the Stand By diver, especially when in these emergency circumstances the divers gas consumption would increase. Surface supplied divers carry a bail out tank and should the supply of air from the surface stop the diver has enough gas in his bail out to reach the surface. Whereas it has been proved statistically that almost all SCUBA reserve air supply systems have e record of failure in case of emergency.

Communication with the surface: Divers in surface supply routinely have voice communication with the Supervisor on the surface, and increasingly, in addition, a video link. In the past SCUBA divers often had no communication with the surface, and again increasingly either a communication wire is attached to or combined with the lifeline or through water communications are used – bearing in mind their limitations of the latter – providing the safety of constant communication with the surface The advantages of voice communication are: 

• The Supervisor can talk to divers and control the work task to the best advantage.
• The Supervisor can monitor the divers breathing, and so give them immediate assistance in the case of an emergency.
• Divers can communicate with the surface in any kind of problem or difficulty.

Safety of breathing apparatus: There are many variations of SCUBA. Some – particularly using a half mask in work situations - can cause serious problems in an emergency, for example, if a diver loses his regulator. The use of “full face mask” or helmet, with an integrated regulator, can prevent this problem.

Decompression: It is normal for the Supervisor to have responsibility for the decompression profile of a working diver. This is difficult during SCUBA operations as he has no direct knowledge of the divers depth. Computers are often used by recreational divers but in working situations the Supervisor has not access to them, and so thay do not relieve him of his responsibility. It is far safer to use Surface Supplied Equipment which provides the Supervisor with a direct readout of the diver’s depth, and allows him to take direct control of the decompression procedure. 

Mobility: It is a common thought that Divers in SCUBA are more “free” that in Surface Supply. This could be true, but the risks are not acceptable, especially in open water during commercial diving operation. Moreover, in the case of an accident, the recovery operation of the Div er could be seriously compromised adverse currents. As an example, a fatal accident occurred in Livorno on the 24 February 2012, when a SCUBA Diver was carrying out the repair of a mooring in at a depth of 18 metres, when he was dragged to 50 metres depth and lost consciousness. Accidents like that often occurs because of inadequate training, when divers work underwater using recreational techniques. It is really important to underline that ENI Spa, in a letter “HSE/SIC records office 16 dated 21 May 2008”, is in force in Italy, with the title “HSE requirements for subcontractors of diving work”, on page 9 it states “Self contained breathing apparatus (SCUBA) has many limits and intrinsic difficulties (the most efficient and safe method to work underwater is with surface supply diving equipment). Therefore, SCUBA equipment should never be used for commercial purposes connected with construction, repairing and maintenance”. Since 2010 Italian Offshore operations, have been run under the UNI Regulation 1136 and directives of IMCA and ENI. Many fatal accidents have occurred because of inadequate, and the Member of Sicilian Parliament, Mr A. Di Biagio, emphasised this point in the Chamber of Deputies, at a Board meeting on 28 April 2011. During his speech, he pointed out the absence of an adequate regulation, concerning with the last accident, he said: “I assume every responsibility by affirming certain knowledge that the promulgation and application of those rules, should have save the life to that young man”. Since 1977, there have been 10 tries to define a regulation, during different legislatures (8 law proposal and 2 Unified Scripture in 2005 and 2009), but it has never worked. For the above mentioned reasons, in these last years, many Port Authority tried to “manage” this problem, issuing local decrees, worried for the safety of Divers who working without adequate competence. 

SCUBA, however, remains the best alternative for recreational diving in pairs, where the main goal is relaxation and fun and not work, which is restricted to qualified commercial divers, According to ISTAT (the nomenclature and classification of the Professional units In Italy) the qualification “diver”, is listed under metalworkers’ because it is in the category: Craftsmen, skilled workers and farmers, subcategory: Craftsmen and skilled metal workers and assimilated,” under the heading “Divers and working divers” (there is no item for Sports Divers, as is sometimes suggested, wrongly, only for Water Sports). This classification is in full accordance with the European version of the International Classification of Occupations (ISCO-88Com) where divers are always in the category “Metal, machinery and related trades workers - Metal moulders, welders, sheet-metal workers, structural-metal preparers” under the heading of “Underwater workers”.

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