Smaller ships with flammable cargoes need an inert gas system

Feb 24 2022


Global Survival Technology specialist Survitec has welcomed industry initiatives to install Inert Gas (IG) systems to smaller oil and chemical tankers less than 8000dwt.

Acknowledging the positive impact of 2016 amendments to SOLAS, which mandated the fitting of an IG system to newbuild tankers of 8000dwt and above, 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, Survitec’s Maritime Protection brand said: “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 said 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 said. “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 concentrations are less than 30% of the lower flammable limit.

 

Ohrn said that given the mass and energy of an explosion at a shore-based terminal or port storage facility, a number of operators are making it compulsory for tankers to be inerted prior to entering the facility.

 

“I think the transportation side of the industry can learn from the ports and storage terminal side. When it comes to safety there should be no debate, no discussion. Safety comes first.”



Related News

Can inert gas systems be included in decarbonisation drives?

(Oct 07 2021)

Inert gas systems themselves use energy. The gas needs to be provided for inerting at the same time as the tanks are emptied, and inert gas cannot be stored onboard, with the volumes so large. Sometimes gas or fuel is burned specifically to create th...



Høglund awarded contract to deliver Fuel Gas Supply System for four Utkilen chemical tankers

(Sep 02 2021)

Høglund and partner Skarweld will retrofit four sister chemical tankers with a turnkey gas solution - whilst the vessels are in operation.



HØGLUND to supply fuel gas systems for four crude oil tankers

(Apr 14 2021)

Høglund wins new contract to deliver Fuel Gas Supply Systems (FGSS) for Bank of Communications Financial Leasing (BoComm Leasing)-owned LR II tankers chartered by Shell.



Sohar tanker turnarounds enhanced

(Mar 14 2014)

Oiltanking Odfjell Terminals Oman (OOTO) has commissioned additional pipeline infrastructure at Sohar in order to reduce jetty turnround times.



June July 2022

SIRE 2.0 - OCIMF and Columbia Ship Management perspective; seafarer mental health; EU ETS costs; 33 years after Exxon Valdez; resolving BWTS problems