Q. When a smartphone is advertised as waterproof, how do they verify that claim?
A. When hawking the water worthiness of their products, most smartphone manufacturers cite the results of IP, or ingress protection, testing. Not to be confused with the popular augmented-reality game, the “ingress” here comes from the Latin “ingressus” from the verb “ingredior” — which means “go into or enter.”
So as you may expect by now, the IP standardized test is all about how much liquid and dust a device can keep out. Phone makers typically list a product’s results as its IP rating under the International Electrotechnical Commission’s 60529 standard.
For its recent Galaxy devices, Samsung touts “an international standard rating of IP68” and says the Galaxy S7 and later models are “deemed fit enough to withstand dust, dirt and sand, and are resistant to submersion up to a maximum depth of 1.5 meters underwater for up to 30 minutes” — which should protect it from the dreaded Toilet Drop.
As for those numbers, the first digit in the rating refers to the level of protection from solid substances and is measured on scale of 0 (no protection) to 6, with a 6 meaning no dust enters the device for two to eight hours of exposure. The second number refers to water and is measured on a scale of 0 to 9. A rating of 8 designates protection against water immersion under pressure for long periods, and a 9 rating means the object can also hold up against high-pressure water jets.
Apple’s support guide regarding the water and dust resistance of the iPhone 7 and later lists an IP67 rating. The company cautions users that “splash, water and dust resistance are not permanent conditions, and resistance might decrease as a result of normal wear,” and that “liquid damage is not covered under warranty.” Apple also warns against using the iPhone while swimming, surfing, riding a water scooter, showering or sitting in a steam room; Google has similar advice for owners of its Pixel 2 phones.
Although “waterproof” is used in some advertising, the term “water-resistant” is a more accurate term. If you need to use your phone around liquid environments, consider keeping it in a sturdy watertight case (or a sealed plastic bag), even if your model has a high IP rating.
Personal Tech invites questions about computer-based technology to firstname.lastname@example.org. This column will answer questions of general interest, but letters cannot be answered individually.