Gard, the Norwegian-headquartered marine insurance firm, has recently published research into propeller shaft aft seal damage, which noted a “significant increase” in failures following the 2013 introduction by the US EPA of new Vessel General Permit (VGP) rules.

According to Gard, the increase in the number of seal failures directly correlates with the increase in the use of approved synthetic lubricants – these lubricants are among those in compliance with US EPA regulations.

Gard’s research, published in October 2023, has taken a deep dive into the data around the shaftline damage claims it has processed over the last 10 years. Its research shows that as many as 80% of the incidents Gard investigated involved stern tube seal failures where an EAL was in use.