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REGULATION
Ensuring the safety of ships at sea has always been of paramount importance and industry initiatives to install inert gas system on oil and chemical tanks of less than 8,000 dwt have been welcomed by survival technology specialists such as Survitec
PUTTING SAFETY FIRST Amendments to the safety of life at sea convention SOLAS were introduced in 2016 which made the fitting of an inert gas system to newbuild tankers of 8,000dwt and above mandatory. Survitec says it has seen a number of IG installations to smaller vessels following recent industry calls for a revision of the rules to include all tanker sizes. Bernt Ohrn, managing director for Survitec’s Maritime Protection brand says: “The amendments written into SOLAS II-2/4.5.5 and II-2/16.3.3 have gone a long way in preventing fatal explosions aboard larger oil and chemical carriers but we do recommend that operators of existing and smaller oil tankers not already covered by the SOLAS requirements should consider installing a system. “If you are carrying a cargo with a flashpoint of 60°C or less, then you really should have an inert gas system onboard.” Prior to 2016, only oil tankers of 20,000dwt were required to have an IG system installed, but the rules were revised after a spate of serious incidents,
including 2004’s fatal explosion aboard the Bow Mariner. A number of incidents involving vessels of smaller tonnage, however, led to calls for another revision to include all oil and chemical tankers, irrespective of size. Referring to an inter-industry working group study published in 2017, Ohrn says the majority of reported incidents occurred during tank cleaning, venting or gas freeing. And in several cases, the tank atmosphere for non-inerted tanks had not been evaluated or was not being monitored. “These incidents are avoidable, as reports show,” Ohrn says. “The installation of an inert gas system on tankers of all sizes that carry flammable cargoes is both technically and operationally feasible, yet only a small percentage of the global tanker fleet has installed technology designed to purge cargo spaces of hazardous vapour.” An IG system is used to remove oxygen in a space with hydrocarbon vapours in cargo tanks to less than 8% by volume. Where tankers are not fitted with the system, flammable vapour is vented until outlet
C L E A N S H I P P I N G INTERNATIONAL – Summer 2022
