When selecting and purchasing electronics and electrical equipment for your boat, you may notice many products are marketed as "waterproof" or "water-resistant" followed by a string of letters and numbers like “IP65”. This rating can apply to anything that uses electrical power to function, from something as simple as an on/off switch or an LED light up to more complex electronics like multi-function displays or battery chargers and converters. But what exactly does that rating mean?

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Key Takeaways
An ingress protection (IP) rating indicates how well a device is protected against water and dust. Defined by the International Electrotechnical Commission (IEC), IP ratings provide a guideline to the degree of protection provided by mechanical casings and electrical enclosures against the intrusion of solids and liquids.
Because electric and electronic equipment can deteriorate or malfunction when water or dust enters the device, it is important to understand exactly how tight the seal is on any given piece of electrical equipment beyond just “water-resistant” or “waterproof,” which is why the IEC developed this standard.
An IP rating is broken down to two numbers, the first indicating the device’s protection against ingress of solids like sand, salt and dust, while the second number indicates the device’s protection against ingress of liquids. The charts below define the level of protection associated with each number.
First Numeral | Solid Object Protection |
|---|---|
0 | No protection |
1 | Protected against solids 50mm in diameter and larger |
2 | Protected against solids 12.5mm in diameter and larger |
3 | Protected against solids 2.5mm in diameter and larger |
4 | Protected against solids 1mm in diameter and larger |
5 | Dust-protected (some dust may get in, but won’t harm the device) |
6 | Dust-tight (no ingress of solids) |
Second Numeral | Water Protection | Definition |
|---|---|---|
0 | No protection | No protection |
1 | Protected against vertically falling water drops | Vertically falling drops shall have no harmful effects |
2 | Protected against vertically falling water drops when enclosure tilted up to 15° | Vertically falling drops shall have no harmful effects when the enclosure is tilted at any angle up to 15° on either side of the vertical |
3 | Protected against spraying water | Water sprayed at an angle up to 60° on either side of the vertical shall have no harmful effects |
4 | Protected against splashing waters | Water splashed against the enclosure from any direction shall have no harmful effects |
5 | Protected against water jets | Water projected in jets against the enclosure from any direction shall have no harmful effects |
6 | Protected against powerful water jets | Water projected in powerful jets against the enclosure from any direction shall have no harmful effects |
7 | Protected against the effects of temporary immersion in water | Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is temporarily immersed in water under standardized conditions of pressure and time |
8 | Protected against the effects of continuous immersion in water | Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is continuously immersed in water under conditions which shall be agreed between manufacturer and user but which are more severe than for numeral 7 |
9 | Protected against high pressure and temperature water jets | Water projected at high pressure and high temperature against the enclosure from any direction shall not have harmful effects |
When shopping for marine electronics, you'll encounter IP ratings displayed in various ways on product packaging and specifications. The rating always follows the same format: "IP" followed by two digits, such as IP67 or IP68.
The first digit (0-6) tells you how well the device resists solid particles like dust, sand, and salt crystals that are common in marine environments. A rating of IP6X means the device is completely dust-tight, which is ideal for boats where salt spray can leave residue on everything.
The second digit (0-8) indicates liquid protection levels. For marine applications, you'll typically want to see ratings of IP65 or higher. An IPX7 rating means the device can handle temporary submersion up to one meter, while an IPX8 rating indicates it can withstand continuous submersion beyond one meter depth.
Look for these ratings on product labels, specification sheets, or stamped directly onto the device housing. If you can't find the IP rating clearly displayed, contact the manufacturer before installation - this information is crucial for marine safety and equipment longevity.
Many boat owners fall into common traps when interpreting IP ratings, which can lead to equipment failure and safety issues. One of the biggest misconceptions is that "waterproof" means invincible - even IP68-rated devices have limits and can fail if those limits are exceeded.
Another frequent mistake is assuming that higher numbers are always better, regardless of cost or application. An interior cabin light doesn't need IP68 protection, and paying extra for that level of protection won't improve performance while unnecessarily increasing your equipment costs.
Some boaters believe that IP ratings are permanent and unchangeable. In reality, seals and gaskets degrade over time, especially in harsh marine environments with constant UV exposure and temperature fluctuations. Regular maintenance and seal replacement are essential to maintain the original IP rating.
Perhaps most dangerously, some assume that any IP-rated device can handle high-pressure water like dock hoses or pressure washers. Even IP67-rated equipment may fail under direct high-pressure spray, as these ratings are tested under specific controlled conditions that don't always match real-world marine scenarios.
Ingress protection serves as the first line of defense between your valuable marine electronics and the harsh realities of the boating environment. Without adequate protection, even the most advanced navigation systems, lighting, and electrical components become vulnerable to the very elements they're designed to help you navigate. Salt spray creates conductive pathways that can cause short circuits, while fine sand and salt crystals act like abrasives that can work their way into the smallest openings, gradually degrading internal components.
The consequences of poor ingress protection extend far beyond simple equipment replacement costs and can impact multiple aspects of your boating experience:
Understanding and respecting ingress protection requirements isn't just about following manufacturer specifications - it's about ensuring your electronics can perform reliably, whether you're enjoying a routine day on the water or facing challenging conditions where equipment failure becomes a safety concern.
Selecting inadequate IP protection for your marine electronics can result in costly and potentially dangerous consequences. Water intrusion into electrical systems doesn't just mean replacing a device - it can cause short circuits that damage connected equipment throughout your boat's electrical system.
Corrosion is another serious concern when moisture enters inadequately protected devices. Salt water is particularly aggressive, and even small amounts can cause internal components to corrode rapidly, leading to intermittent failures that are difficult to diagnose and can leave you stranded.
Safety risks multiply when critical navigation or communication equipment fails due to water damage. A GPS chartplotter or VHF radio that stops working during rough weather or emergency situations puts your crew and vessel at serious risk.
From a financial perspective, insurance companies may deny claims for water damage if equipment wasn't properly rated for its installation location. Additionally, repeated equipment failures due to inadequate IP ratings can quickly exceed the cost of purchasing properly rated devices from the start.
Different areas of your boat require different levels of ingress protection based on their exposure to water and environmental conditions. Understanding these zones helps you select appropriate equipment and avoid overspending on unnecessary protection levels.
Below Waterline and Underwater Applications: Any equipment mounted below the waterline or designed for underwater use must have IP68 ratings to handle continuous submersion and water pressure.
The main consideration regarding IP ratings is where on the boat the device in question will be installed. Let’s take LED lights as an example. An interior cabin light does not need to be waterproof as it will not be directly exposed to the elements. For a deck light or navigation light that might get sprayed down by a hose or take direct sea-spray and waves, you wouldn’t want anything less than IP65 and a rating of IP66 or IP67 would be preferable. Something mounted below the waterline on the exterior of the hull, like an underwater light, must be rated IP68 or higher.

The same should be taken into consideration for something like a battery charger mounted in wet locker, bilge or under the helm in a center console where the console itself may not be entirely sealed off from the elements outside. If there’s any chance of water splashing into the location where it’s mounted, you’ll want to have a charger that’s rated at least IP65 to avoid the risk of frying it if it gets wet. Something like a multi-function display that’s mounted on an external helm like a center console or flybridge should be at least IP66 or higher.
Always be sure to check on IP ratings with the manufacturer of a given device once you’ve determined the installation location, as many companies offer the same or similar devices with varying IP ratings. If you have questions or would like any additional information on the IP ratings of Imtra products, please feel free to contact us or check the specifications tab on any product page.
Generally, no. IP ratings are determined by the device's original design and manufacturing. While you can add external enclosures for additional protection, this doesn't change the device's official IP rating and may affect warranty coverage.
Yes, many marine insurance policies require equipment to meet minimum IP standards for their installation locations. Using inadequately rated equipment may void coverage for related damage claims.
Inspect seals and gaskets annually, and after any significant weather events. Replace gaskets every 2-3 years in harsh marine environments, or sooner if you notice cracking or hardening.
Yes, IP ratings adhere to the International Electrotechnical Commission (IEC) standard, making them consistent globally. However, always verify with manufacturers that their testing meets IEC standards.
While the IP rating technically applies to both, saltwater is much more corrosive than freshwater. Consider choosing a higher IP rating than the minimum requirements when operating primarily in saltwater conditions.
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