Amendments to SOLAS - Inert Gas System Requirements on Board New Build Tankers From 1 January 2016

The IMO Sub-Committee on Fire Protection (FP) met for its 56th session between 7 to 11 January 2013.

The FP then submitted a package of draft SOLAS amendments to the Maritime Safety Committee (MSC 92), for approval and adoption of measures to prevent explosions on oil and chemical tankers transporting low-flashpoint (less than 60°C) cargoes. The amendments to SOLAS come into force on 1 January 2016.

The development of the draft amendments followed many years of work aimed at preventing explosions on oil and chemical tankers that transport low-flashpoint cargoes and follow recommendations made by an Inter-Industry Working Group (IIWG) that was established to study incidents of fires and explosions on chemical and product tankers.

The IIWG included the European Chemical Industry Council (CEFIC), the International Association of Classification Societies (IACS), the International Association of Ports and Harbours (IAPH), the International Chamber of Shipping Limited (ICS), the International Association of Independent Tanker Owners (INTERTANKO), the International Parcel Tankers Association (IPTA), the Oil Companies International Marine Forum (OCIMF) and the International Group of P&I Clubs.

The requirements will impact on the design and operation of small oil and chemical tankers due to the costs involved in providing suitable type-approved inert gas systems (IGS) onboard, although this is dependent on the type of vessel.

Oil and Chemical Tankers

The amendments to SOLAS regulations II-2/4.5.5 and II 2/16.3.3 require an inert gas system to be fitted on all new oil and chemical tankers of 8,000 dwt and above, (when transporting low-flash point cargoes of <60°C). Oil tankers above 20,000 dwt were already required to install such systems.

For tankers fitted with exhaust gas inerting systems, the application of inert gas must be carried out during loading, on passage, unloading, tank cleaning and purging prior to gas freeing.

However, for chemical tankers, the application of inert gas may take place after the cargo tank has been loaded, but before the commencement of unloading (only if nitrogen is used as the inerting medium) and shall continue to be applied until that cargo tank has been purged of all flammable vapours before gas freeing.

The oxygen limit (all tankers) for inert gas supplied to cargo tanks has also been lowered from 8% to 5% for new systems.

Chemical Tankers

The exemption for existing chemical tankers with tank volumes not exceeding 3,000 m3, fitted with tank cleaning machines with a throughput not exceeding 17.5 m3/h (per nozzle) and a total combined throughput not exceeding 110 m3/h, does not apply to chemical tankers delivered after 1st January 2016.

Related draft amendments to the International Code for Fire Safety Systems (FSS Code) were also agreed, resulting in a complete replacement of chapter 15 (Inert Gas Systems).

IMO MSC-2 entitled “Draft Amendments to SOLAS Regulations II-2/4 and II-2/16” can be read here.