Page 58: of Marine Technology Magazine (September 2014)

S ince the fi rst deployment of in-situ monitoring instru- mentation, biofouling has been a problem. Without an effective solution, people have historically had to accept the limits biofouling imposes on ocean sens- ing work, with signifi cant repercussions. When instrumen- tation is deployed in-situ, the value of the data taken during the deployment corresponds with the longevity: information gleaned from a longer deployment is often more useful than information from one of a shorter term. When marine growth begins encroaching upon sensors it alters the readings, ren- dering the data collected inaccurate. Biofouling can encumber instrumentation within a few weeks, severely limiting the du- ration of deployments and hindering environmental monitor- ing efforts.

Ocean observatory networks around the world are growing as efforts increase to monitor the world’s oceans. The technol- ogy used on observatories is allowing more in-depth research of these bodies of water than ever before. Since these under- water networks have in-situ instrumentation deployed for long periods of time, biofouling control is needed to keep sensor readings accurate and camera footage clear. Without biofoul- ing control to maintain sensors and camera lenses, ocean ob- servatories yield information of diminishing reliability over time.

Current antifouling methods have substantial drawbacks.

Those encountering biofouling must choose between using toxic chemicals which harm the waters they are trying to mon- itor, and methods of limited effi cacy, such as mechanical wip- ers and copper plating. Vulnerable to malfunction and fouling themselves, mechanical wipers are also unsuitable for sensi- tive lenses and surfaces with complex contours. Copper has a limited lifespan as an anti-foulant; its effectiveness decreases over time. Signifi cant technological advancements have been made in ocean monitoring instrumentation, but their full po- tential has not been reached due to the shortcomings of these antifouling methods.

Although the potential of UV radiation as an anti-foulant has been known for over three decades, this year marks the fi rst it is commercially available. Looking to eliminate the lead- ing cause of sensor drift, instrumentation manufacturer AML

Oceanographic of Sidney, BC, Canada, began researching the prospect of UV light as a viable method of biofouling con- trol for in-situ sensors. However, based on the encouraging results, AML broadened the scope of this method to include other devices installed underwater.

AML established the effi cacy of UV light as a method of biofouling control fi rst with fundamental tests of the tech- nology, and then further testing with more advanced product prototypes in various environments. Once the basic technol- ogy was proven at the Institute of Ocean Sciences in Sidney,

BC, and Ocean Network Canada’s (ONC) observatory at Fol- ger Pinnacle off the west coast of Vancouver Island, an early

Biofouling Foiled

UV Light Harnessed for Biofouling Control

By Jehan Zouak, Marketing Coordinator, Chris Bueley, Mechanical Engineer &

Pete Reedeker, Director of Sales & Marketing, AML (Photo cour tesy of Adrian R ound, Dir . of Obser v ator y Operations, ONC)

September 2014 58 MTR

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