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Just how tough is your phone case? We break down IP ratings, military standards

What are IP ratings
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Most flagship phones these days boast some level of water-resistance, and you’ll find so-called IP ratings on everything from the Apple iPhone XS to the Huawei Mate 20 Pro. But that got us wondering: Just what do manufacturers mean when they use terms like “waterproof” and “water-resistant?” What constitutes a “rugged” device? And just how many times can you drop your phone in the toilet before you can expect it to bite the dust?

As it turns out, some terms that describe a phone’s ruggedness are actually standardized, and there’s a whole lot more to them than meets the eye. IP ratings measure a smartphone’s resistance to water, dust, and other particles, for example, while military specs describe their structural integrity. Some certifications are a little less precise than others, but taken together, they give a rough idea of how a smartphone will hold up against the elements.

Here’s everything you need to know about IP ratings and MIL-STD certifications.

The ratings behind a ‘rugged’ product

Unihertz Atom Review
Unihertz Atom Mark Jansen/Digital Trends

“Rugged” is just a word, a marketing ploy as meaningless as “summer-proof,” “water-resistant,” and “dustproof,”. All make nice bullet points on a phone’s spec sheet, but they aren’t all that descriptive — “rugged” and “water-resistant” devices can short just as easily as “non-rugged” devices when they fall into water (as well as shatter when they hit the concrete).

A certification is something completely different. When a phone has a certified rating of some sort, a third party has conducted tests to ensure that it can survive conditions like hard falls, dusty shelves, extreme heat, certain kinds of radiation, and deep pools of water.

Phone, tablet, and PC manufacturers measure the ruggedness of devices using two systems of standards: The Ingress Protection (IP) Rating, published by the International Electrotechnical Commission; and the Military Specification or Military Standard (MIL-STD), which is developed by arms of the U.S. Military and Department of Defense.

Ingress Protection Rating

sony xperia xz3 front
Sony Xperia XZ3 Simon Hill/Digital Trends

A smartphone’s Ingress Protection Rating is determined by how well it holds up against dirt, dust, and water. Ratings range from 1 to 6 for dust and dirt and 1 to 9 for water, with the first and second digit in the rating indicating how well it withstands exposure to solid particles and liquids, respectively. The maximum rating for solid objects, IP 6, means it lets in very little dust and dirt, and a water-resistance rating of 8 indicates it can be submerged in water for minutes at a time. A phone with those specs would earn an IP68 rating.

To make matters more complicated, a high IP rating doesn’t necessarily mean dust, water, or debris won’t enter a phone’s enclosure. Rather, it indicates that when dust and water does make its way through a phone’s seams, it won’t enter in sufficient quantities to cause malfunction. So the IP67-rated iPhone XR will not be as resistant to water entry as the IP68-rated iPhone XS Max, even though both phones will come out of the pool just as wet.

However, IP ratings are not all-encompassing, and phones need not pass every lower test to snag a higher rating. For example, for a smartphone to nab the the coveted IP68 certification, it has to pass the tests for IPX7 and 8 — but is not required to test for water jets on the IPX5 and 6 levels.

That’s the reason you sometimes see a smartphone with multiple IP-ratings. The Sony Xperia XZ3 is rated both IP65 and IP68, which signifies that it’s resistant against total immersion and high-pressure water jets.

Here’s a breakdown of the ratings for solid foreign objects.

Level

Object size it protects against

Effective against

0 Not protected No protection against solid objects
1 >50 millimeter Protection against large surfaces like the back of the hand
2 >12.5 millimeter Protection against finger-sized objects
3 >2.5 millimeter Protection against thick wires and like objects
4 >1 millimeter Protection against wires, screws, etc.
5 Dust protected Some protection against dust and complete protection against contact
6 Dust tight Complete protection against dust and contact

There’s a separate chart for water ratings. Note that they’re described in terms of “water nozzles” and “jets” — a manufacturer like Sony, Apple, or HTC can choose to expose their phone to high-pressure blasts of water from an industrial hose, and see how it fares over time.

Level

Object size it protects against

Effective against

0 Not protected Nothing
1 Dripping water Protection against 10 minutes of dripping water
2 Dripping water when tilted up to 15 degrees Protection against 10 minutes of dripping water when tilted 15 degrees from normal position
3 Spraying water Protection against 5 minutes of spraying water at any angle up to 60 degrees from the vertical
4 Splashing water Protection against 5 minutes of splashing water
5 Water jets Protected against at least 3 minutes of water spraying from a 6.3-millimeter nozzle from any direction
6 Powerful water jets Protection against at least 3 minutes of water spraying from a powerful nozzle (12.5-millimeter) from any direction
7 Immersion up to 1 meter Protection against 30 minutes of water up to 1 meter of submersion
8 Immersion beyond 1 meter Protection against continuous immersion in water up to depth specified by the manufacturer
9 High-pressure,
close-range jets
Protection against continuous high-pressure, close-range jets of water from any direction — including high-temperature steam jets

Here’s a chart of some of the top phones in terms of water and dust resistance:

Phone

IP rating

Effective against

iPhone XS IP68 Complete protection against dust and contact; protection against continuous immersion in water up to depth specified by the manufacturer
Samsung Galaxy S9  IP68 Complete protection against dust and contact; protection against continuous immersion in water up to depth specified by the manufacturer
Sony Xperia XZ3 IP68/IP65 Complete protection against dust and contact; protection against continuous immersion in water up to depth specified by the manufacturer; protected against at least 3 minutes of water spraying from a 6.3-millimeter nozzle from any direction
Caterpillar CAT S61 IP68/IP69 Complete protection against dust and contact; protection against continuous immersion in water up to depth specified by the manufacturer; protection against continuous high-pressure, close-range jets of water from any direction — including high-temperature steam jets
LifeProof FRE (iPhone case) IP68 Complete protection against dust and contact; protection against continuous immersion in water up to depth specified by the manufacturer

For an idea of how an IP certification is determined, take a look at this video of a test being conducted on behalf of electronics company Siemens. It ended up getting a an IP67 rating — the same rating as the iPhone XR — which means it’s been shown to withstand exposure both to objects and up to about three feet (or one meter) of water for 30 minutes.

Military specifications and standards

what are ip ratings

Military Specifications and Standards number in the hundreds and certify a product’s ability to handle specific scenarios. For example, there are MIL-STD-810Gs that certify products to handle nuclear radiation exposure, drops onto concrete, rapid temperature changes, and a wide number of other environmental conditions.

Test Method 500.5 Low Pressure (Altitude) Test Method 501.5 High Temperature Test Method 502.5 Low Temperature
Test Method 503.5 Temperature Shock Test Method 504.1 Contamination by Fluids Test Method 505.5 Solar Radiation (sunshine)
Test Method 506.5 Rain Test Method 507.5 Humidity Test Method 508.6 Fungus
Test Method 509.5 Salt Fog Test Method 510.5 Sand and Dust Test Method 511.5 Explosive Atmosphere
Test Method 512.5 Immersion Test Method 513.6 Acceleration Test Method 514.6 Vibration
Test Method 515.6 Acoustic Noise Test Method 516.6 Shock Test Method 517.1 Pyroshock
Test Method 518.1 Acidic Atmosphere Test Method 519.6 Gunfire Shock Test Method 520.3 Temperature, Humidity, Vibration, and Altitude
Test Method 521.3 Icing/Freezing Rain Test Method 522.1 Ballistic Shock Test Method 523.3 Vibro-Acoustic/Temperature
Test Method 524 Freeze / Thaw Test Method 525 Time Waveform Replication Test Method 526 Rail Impact
Test Method 526 Rail Impact Test Method 527 Multi-Exciter Test Method 528 Mechanical Vibrations of Shipboard Equipment (Type I – Environmental and Type II – Internally Excited)

Military Standards ratings comprise an exhaustive number of certifications, but there’s a big problem: They aren’t standardized. Manufacturers can conduct different tests and end up arriving at the same conclusion, which is partly the fault of the 810G system — it’s meant to be flexible depending on the device being tested. But it makes it a little harder to know what to expect.

Take the 810G’s “temperature shock” certification, for instance, which measures a device’s ability to withstand fluctuating temperatures. The temperature range isn’t defined, and neither is the amount of time, leaving plenty of wiggle room for a smartphone maker to claim that its handset is 810G-certified without having to explain what that really means.

The 810G’s “solar radiation” standard is the same. Basically, any phone that can survive roughly three days of direct exposure to sunlight without becoming nonfunctional (or discolored) before, during, or after the test meets the device’s requirements. That’s not exactly the most useful measure.

Perhaps the most common standard for rugged devices is MIL-STD-810G, which is an umbrella designation with a number of durability subcategories — namely protection against drops and falls. This pops up a lot on phone cases designed to offer drop protection, but military drop test standards vary depending on the tests case manufacturers run on their rugged cases.

More than IP67

CAT S61 back full
Andy Boxall/Digital Trends

For devices like the iPhone XR, certification goes as far as dust, dirt, and 1 meter of water. But if you drop an iPhone XR onto concrete from 4 feet up, don’t expect it to come out the other end unscathed.

Perhaps more importantly, just because a phone has achieved a certain certification doesn’t mean it’ll hold up to abuse. Manufacturers conduct tests under lab conditions far different than the real-life scenarios you’re likely to find yourself in. In one particularly egregious example, Sony sent marketing materials that showed the company’s IP68-certified Xperia phones being used underwater … accompanied by a warning not to use them as depicted.

That’s not to dismiss IP ratings and military certifications wholesale. As an informed consumer, you should absolutely find what ratings your device has before you buy it. But you should also take them with a grain of salt. No device is rugged in every way, and water, dust, and drop tests are conducted in labs — not the real world.

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