Decoding the IP Rating: Understanding dust and water resistance

Decoding the IP Rating: Understanding dust and water resistance

I realised recently when reviewing a phone that it would probably be useful to break down in detail exactly what an IP rating is.

I mean, it’s almost always explained in context of a product’s specs or through a review that the IP rating explains the level of dust and water resistance of the product.

But what does it actually mean? What are the different numbers available? What do they mean? What does an X symbol stand for? 

That’s what this guide is for. Bookmark if you have to, but my goal here is to break down everything you need to know about the IP rating, and why it’s important. The last thing you want to do is take a gadget you think is waterproof beyond its rating and end up with a waterlogged paperweight.

What is IP, anyway?

No, it’s not “intellectual Property”, at least not in this context.

IP stands for “Ingress Protection”. That means it is a measure of how well an electronic or mechanical device resists ingress from foreign bodies like dust or dirt, and how well it resists moisture.

When a device communicates its IP rating, it is typically listed with the letters IP, followed by two numbers.

I’ll break down the specifics of each number below, but for now just know that the first digital is used to describe the device’s resistance to solids, like dust, while the second refers to its resistance to liquids.

Occasionally, you will see an “X” in there as well. This means that the device hasn’t been rated for that particular resistance. 

So, for example, IPX7 means that the device has been rated to resist liquid, but has no rating for dust or dirt protection.

Similarly, a gadget rated IP5X is going to resist dust, but hasn’t been rated to resist water getting inside.

Protection from dust and debris

As mentioned above, the first digit in an IP rating refers to the protection against solid particles, like dust, dirt, and sand.

The numbers range from 0 to 6, with six being the highest rating available and 0 (or X) meaning that it has not been rated for ingress protection against solid particles.

When it comes to technology, largely you will be looking at numbers between 4 and 6. Numbers lower than four are typically more appropriate for mechanical devices rather than electronics.

You can see the full breakdown of each rating and what it means in this table:

IP Dust ratingWhat it means
0 (or X)X is used when the product’s rating has not been specified
0 is used when the product offers no protection from solids
1Protected against solid objects larger than 50 mm, like the back of your hand
2Protected against solid objects over 12 mm, like fingers and hands
3Protected against solid objects bigger than 2.5 mm in size, like large screwdrivers or thick wires
4Protected against solid objects larger than 1 mm, like most wires, small tools and insects
5Limited protection against dust, but there shouldn’t be enough ingress to impact performance 
6Complete protection from dust

Protection from liquids

While the first digit refers to the solid matter that can get into cracks and crevices, the second digit is all about liquids.

With consumer technology, liquids are typically the one you want to worry a bit more about. Water getting into your electronics is typically going to damage the product much worse than some dust.

So getting your smart device with a water IP rating is a good idea to protect it from accidental spillages, or falling in the pool.

Like the dust rating though, there’s a scale of numbers, though this time the scale runs from 0 to 9.

I’ve broken down the liquid ratings in the table below:

IP Liquid ratingWhat it means
0 (or X)X is used when the product’s rating has not been specified
0 is used when the product offers no liquid intrusion protection
1Protected against water drops falling vertically downwards
2Protected against vertically falling water drops tilted at up to 15 degrees from the vertical
3Protected against sprays of water up to 60 degrees from the vertical
4Protected against splashes of water from any direction
5Protected against low-pressure jets of water (tested at 12.5 Litres per minute through a 6.3 mm nozzle)
6Protected against high-pressure water jets of water (tested at 100 litres per minute through a 12.5 mm nozzle)
7Protected against immersion in water up to one meter deep for 30 minutes
8Protected against immersion in water between one and three metres under pressure for extended periods of time, which can vary depending on the manufacturer
9KProtected against high pressure hot water jets (tested at 14–16 litres per minute with 80ºC water at 10-15 cm range

What’s particularly interesting about the water ingress rating is that it isn’t actually a scale. A device that is rated IPX7 doesn’t mean it’s rated for IPX6, as the tests reflect different circumstances.

For consumer technology devices, it’s really the IPX7 and IPX8 immersion ratings you want to look for. These are the ones that mean you can drop the phone in the pool (or the toilet) and it will still work afterwards.

It’s also important to remember that these ratings don’t mean you should take your phone swimming unprotected. IP ratings are tested using fresh water, and the salt water of the ocean or chlorinated water of a pool could corrode your device, even if it has an IP water rating.

Why IP ratings are important

The thing about IP ratings is that they aren’t really that essential. You can buy a phone or a smartwatch that doesn’t offer an IP rating, and it will typically work perfectly fine.

In some cases, you’ll even find that devices may not have an official IP rating, but they are manufactured to the same specifications. 

Sadly, there’s no official industry body for handling IP specifications, so the responsibility for testing falls on the manufacturer, as does the costs.

So smaller manufacturers might skip the rating process to save costs, even if the product could receive a rating if it was tested.

That said, there’s still a peace of mind that comes from having a device rated against water ingress when you accidentally drop it in the sink while you’re washing up.

As with any type of purchase, you should consider your individual needs before you hand over your cash.