What Does It Mean for an Electronic Device to Be Waterproof?

What does it mean for an electronic device to be waterproof? Here's a brief overview of the IP code for waterproofing and dust proofing devices with some information on NEMA enclosure types.

With more and more electronic devices claiming that they are waterproof or water-resistant, how are you supposed to know if your phone can be dropped in a pool and survive? How can you know if your laptop will fry if coffee is spilled on the keyboard?

Luckily there are standards to help us: IP codes and NEMA enclosure types. Let's talk about what "waterproof" truly means for electronics.

The Sony Xperia ZR, a "waterproof" and "dust resistant" (IP58/IP55) phone. Image courtesy of Sony Mobile.

IP Codes

No, the "IP" in "IP codes" does not stand for Internet Protocol as many would think at first glance. It stands for International Protection Marking (with the M missing from the acronym).
This is the International Electrotechnical Commission (IEC) standard 60529. The goal of this standard is to describe and classify the enclosures used for electrical equipment based on how protective they are of the electronics inside.

While IP codes theoretically make it easier for consumers to determine how well protected their electronics are, the classification can vary from one type of equipment to another and from one situation to the next. Therefore, the standard isn't capable of giving a definite degree of protection on its own. For a full picture of how protected a piece of equipment is, the manufacturer of the equipment must provide additional information.

Essentially, the IP code standard is only as useful as manufacturers are cooperative. They must adopt the IP code system and share information about their equipment in order for the code standard to provide a meaningful guide to electronic enclosures.

The Structure of an IP Code

An IP code always has ‘IP’ as the first two characters, with two digits following. There can be additional letters at the end of the code, indicating whether the device is oil resistant (f) or high voltage (H). These letters can also indicate whether the device was moving (M) or standing still (S) during the water test, as well as weather conditions (W).
The two digits are what actually provide the specific degree of protection. The first digit tells us the amount of protection against objects and particles, from fingers down to dust. The numbers range from 0 to 6, with 0 being no protection and 6 being dust tight.
Check out the chart below for some more specific details on this first digit.

Chart courtesy of Wikipedia. Click to enlarge.

The second digit specifies the water resistance. The number system is a little different here, as there are some qualifiers. The scale goes from 0 to 9K, with 0 being no protection, to 9K being protected against extremely intense water pressure.
Here is a chart with the different levels associated with an IP code's second digit:

Chart courtesy of R&M Electrical. Click to enlarge.

The levels that would affect most people are 7 and 8 since these deal mainly with submersion (versus getting blasted with a firehose). Level 7 is immersion up to 1 meter for 30 minutes and level 8 is immersion in water deeper than 1 meter for a time period determined by the manufacturer.
Unfortunately, this gives a very vague answer to “how waterproof is my phone?” Unless the manufacturer decides to disclose the specific values for a level 8 rating, then the consumer simply won’t know.

NEMA Enclosure Types

NEMA is the National Electrical Manufacturers Association, a group proclaiming themselves to be "the association of electrical equipment and medical imaging manufacturers". NEMA's standard for electrical equipment enclosures is geared more towards industrial regulations but it's a relevant system when determining levels of waterproofing.

NEMA enclosure ratings are another standard—one with 20 different types—for various ratings which combine the dust and water IP codes.

Example of the progression of NEMA enclosure types and their corresponding protections. Image courtesy of NEMA. Click to enlarge.

The NEMA standards are actually far more comprehensive than that put forth by the IEC. This is because the IEC focuses solely on the infiltration of foreign objects and water where NEMA expands its testing to far more situations. For example, NEMA takes into account condensation specifically rather than just "water". It also looks at oil, vermin damage, frost, and more.
Here's a chart depicting the conversion of NEMA codes to their IEC equivalents:

Chart courtesy of NEMA. Click to enlarge.

Note that the chart cannot convert from IEC to NEMA as there are too many variables in the NEMA standard to make an accurate approximation.

For the full specifications of NEMA enclosure types, check out this PDF from NEMA.

The Ratings of the iPhone 7 and Galaxy S7

To make things a little simpler, let's look at the IP code values.
The iPhone 7 is rated as IP67. The Samsung Galaxy S7 and S7 Active are both rated at IP68. This means that Samsung has specified that they've tested the S7 in 1.5 meters of water for at least 30 minutes.

An immersed iPhone. Screenshot courtesy of Soldier Knows Best.

Both phones are considered “dust tight” and both can last for 30 minutes in 1 meter of water without harm.

As more and more devices claim to be "waterproof", it's a good idea to research your device's rating so you can better understand its limitations.