MARINE insurers are investigating at least two separate incidents involving scrubbers, one of which has been described as “catastrophic”, amid growing concern regarding the extra risks associated with exhaust gas cleaning systems.

Scrubbers have topped the agenda at the annual industry conference of The International Union of Marine Insurance being held in Toronto this week. According to Rama Chandran, chairman of IUMI’s Ocean Hull Committee, a recent spate of scrubber-related incidents are now officially under review as insurers seek clarity over the potential heightened risk involved in vessels fitted with systems.

One of the cases discussed on stage during the conference involved a “catastrophic” engine room fire during a scrubber installation, Paul Hill, a managing director with London-based marine insurance consultants AqualisBraemar told IUMI.

“Any increased machinery on a vessel is going to be an increased risk,” he said, speaking at the Ocean Hull Committee question and answer session.

He provided no further details about the fire, nor an engine room flooding in a vessel cited as a first, separate incident. Both of which have been widely discussed but not independently confirmed as being caused by scrubbers by either the vessel owner or manufacturers involved.

The conference heard that the rise in the use of exhaust gas cleaning systems will increase risk for the hull and machinery sector, alongside the introduction of untested blends of unstable, incompatible lower-sulphur fuel oil which could damage ship engines.

Lloyd's List approached the Clean Shipping Alliance 2020, a lobby group formed last year by major shipping companies that have invested in scrubber technology ahead of the 0.5% sulphur cap, for comment on the issue. “We don’t see it  [EGCS] as any more of a liability than any other equipment in the engine room,” CSA 2020 Chairman Mike Kaczmarek said in a statement..

More than 3,000 scrubbers are estimated to be installed on the world’s largest bulk carriers and tankers by the end of the year, allowing them to use high-sulphur fuel oil and remain compliant with the IMO2020 sulphur cap on bunker fuels that begins in January.

“We are trying to establish as much as possible,” Mr Chandran said of the reports.

“We haven’t got a lot more details of whether there’s been any significant losses on scrubbers… so we don’t know how extensive this is and how systemic, or whether this is specific to one type of scrubber.”

There is intensifying scrutiny of scrubbers amid reports of unexplained corrosion problems to pipework and discharge outlets that need replacement less than six months after installation. Class societies revealed there had been several instances of corrosion to Lloyd’s List last week.

Scrubbers remain untested technology, said Thomas Paterson, a senior vice-president with Canadian shipowner Fednav.

“What we hear from the shipmanagers is not encouraging. We hear of numbers of ships that are struggling to get the systems working, and a number of ships are having to put more crew on board to operate them. So certainly, it’s a big issue.”

Mr Chandran, based with Singapore-based QBE Insurance, likened the issues involving scrubbers to exhaust gas economisers seen in the 1990s.

“We used to have a lot of issues with exhaust gas economisers which fundamentally had some similarities,” he said. “The exhaust gas goes to an economiser before it takes off a bit more of the energy in terms of the efficiency before it comes off into the atmosphere. This has a similar scenario, we’ve got high sulphur being accumulated … in the scrubbers, which could possibly be some degree of catastrophic loss from that unit.”