Switching to biocide-free anti-fouling measures

Dr Burkard Watermann, a zoologist and director of the Research Institute LimnoMar, has been researching the subject of anti-fouling for the German Environmental Protection Agency.

“In the long term, anti-fouling measures must become biocide-free. Not only large companies but also the responsible regulatory authorities are aware that biocide-free solutions are imperative,” said Dr Watermann.

“All anti-fouling biocides which are currently approved by the EU pose risks. There is a strong need for biocide-free solutions and, as a result, research is increasingly focusing on this subject.”

Biocide use

Dr Watermann said that legislation regarding the use of biocides is regionally organised and poses real barriers for many shipping companies and shipyards.

In addition, he said, there will be more and more waters in Europe where anti-fouling systems containing biocides are no longer permitted so the demand for biocide-free solutions is increasing.

Dr Watermann said that there are many positive benefits to switching to biocide-free anti-fouling too.

More choice is now available on the market, whether anti-stick coatings, anti-stick films, hull lifting or cleaning systems or even tarpaulins which are drawn under the boat’s hull, they can all be used in both brackish water and seawater.

Coatings containing biocides, on the other hand, always have to be matched to corresponding salinity of the water because it influences the leaching of the biocide out of the coating.

Dr Watermann has been examining Renolit’s films and performing regular trials for almost three years.

He said that the advantages of fouling release films are generally based on the high quality of the Fluoropolymer layer. As opposed to anti-stick coatings, which are difficult to apply and which yield qualitatively unreliable results, a fouling release film offers maximum good performance.

“In our experience, the performance of such films is equivalent to professionally-applied biocide coatings,” he said.

“Furthermore, if physically damaged, the corresponding areas of such films can be simply cut out, removed and renewed. Repairs to anti-fouling coatings, on the other hand, are considerably more complicated.”

Additionally, anti-fouling coatings containing biocides have to leach to generate the desired effect. In the case of fouling release films, the layers neither separate nor erode.