ABYC Standards for Corrosion Prevention for Your Boat

Owning a boat comes with a range of maintenance and upkeep demands, all of which you’ll want to stay on top of if you want to continue to enjoy regular outings on the water. However, there may be no concern more demanding than corrosion, especially if you take your boat out on saltwater. Because of the way it’s designed, once one part of the vessel starts to break down, several other essential parts tend to go as well, and corrosive damage is irreversible. If you’re not careful, you’ll be looking at replacing expensive parts or else buying a new boat altogether. 

We hate to see this happen, especially when there are steps you can take to prevent this common issue. That’s why we here at Hampton Watercraft and Marine have provided you with a guide to prevent this, based on the American Boat and Yacht Council (ABYC) standards. Check them out and let us know if you need additional advice. We’re in Hampton Bays and Eastport, New York, serving Eastern Long Island.

Breaking Down the Science

First, it’s helpful to know what exactly is going on when we talk about corrosion. The science can be daunting, but some of the fundamental concepts are fairly simple. When we talk about “corrosion” generally, we’re more specifically referring to galvanic corrosion (for these circumstances). 

In galvanic corrosion, two metals of dissimilar electrical potential (materials with widely varying atomic makeup) come into close contact with an electrolyte pool. The pool activates a positive and negative charge between the two materials, essentially creating a battery. One material becomes the cathode (the negatively charged material) and the other becomes the anode (positively charged material). 

Bear with us—we’re almost at the punchline. The cathodic material attracts electrons from the anode, which in turn causes the anode to break down as it loses particles. This is when corrosion happens. Exactly which materials become cathodes and which become anodes are based on where they fall in relation to the noble metals (metals most resistant to corrosion). These noble metals are generally the cathodes, so the less noble metals become anodes. You can find charts outlining where some common boat materials fall on this spectrum.

Keep in mind, this is different from natural oxidation. Oxidation might take place over the course of decades. Galvanic corrosion occurs much, much faster.

Where Will This Happen?

The reason this type of corrosion is so important to pay attention to is because there are few areas where this is more common than you might think. Most often, you’ll encounter this if steel and bronze or steel and aluminum come into contact with saltwater. These metals sometimes interact around the propeller or the mast, if you have one. These will require you to take extra steps if you want to keep using your boat.

ABYC Standards

ABYC has set a series of standards that dictate when your boat is safe from corrosion, depending on the materials you’re working with. These aren’t just guidelines. If you want your boat to be NMMA-certified, these standards must be followed. We highly recommend looking them over to ensure you’re following all the requirements, in order to keep you and your fellow passengers safe (and also protect your pocketbook). 

Sacrificial Anodes

Which brings us to the million-dollar question: what’s a boat owner to do? Galvanic corrosion will happen. You can’t stop that, as it’s a natural, chemical process. However, you can control where it happens. Your boat is going to need sacrificial anodes. Essentially, you’re trying to find a metal that draws the corrosive process to itself and away from essential parts like your propeller and hull. 

Exactly what this material is made out of can depend on your boat and the water you’re in. Traditionally, zinc was the most popular type of sacrificial anode, but this isn’t quite the case anymore. Nowadays, you might see more aluminum and magnesium sacrificial anodes, especially for those who spend more time in brackish waters or freshwater (zinc oxidizes in freshwater). 

What You Need

When you choose an anode material, you’ll need a good multimeter to determine your hull’s potential. Depending on the voltage reading, you’ll want to use ABYC standards to determine exactly how much you need to offset in order to prevent corrosion. Eventually, these sacrificial anodes will need to be replaced or you’ll need to add more as they themselves break down, so keep an eye on them.

That was a lot. We know. And some of you might be thinking it’s a bit out of your skill range. Not to worry! You can contact our service department here at Hampton Watercraft and Marine and we’ll help you get your boat ready for a lifetime on the water. We welcome all patrons from Hampton Bays, Eastport, and Eastern Long Island, New York.