How "wet" is "wet"?

The recent WIRED article regarding the confusion over indicator strips turning pink in humidity has me wondering what we mean by the term “water damage”. Am I putting my phone in danger from water damage when I use it in the bathroom to play the radio while I take a shower? Was it ultimately my own sweat that killed my MP3 player when I used to tuck it into my bra at the gym? And will my e-reader fall prey to the same faults if I keep using it in the kitchen, holding it in one hand whilst stirring the pot of steaming pasta with the other?

We learnt in the recent article, Why does a wet phone die? that electricity in the presence of water can cause electrochemical migration and permanent short circuiting of devices. But surely a bit of steam or sweat is a different matter, even if it is enough to turn an indicator strip pink? Another question for the gang in the P2i Labs, I think.

Can sweat and humidity really cause damage to electronic devices?

When P2i first emerged into the electronics sector, it was on hearing aid devices. These are very expensive, small, pieces of electronics that live behind the ear. A big issue in the hearing aid industry is corrosion damage, as the close proximity to the skin allows for the transferal of sweat and adds to the humidity and amount of moisture in the air around the device. This causes the metals inside the device to have a chemical reaction and begin to oxidize leading to the gradual degradation of the materials. P2i’s nano-coating dramatically reduces this corrosion damage and in just three years P2i went from coating zero to about 60% of the hearing devices produced globally.

How do you know what’s causing the damage?

One of the tests we did with the hearing devices, which we are also doing on smartphones, is known as an ‘accelerated corrosion test’. The idea is that over a period of days, we can mimic what a device is exposed to over its lifetime. The test allows us to introduce phases of increased salt or moisture, followed by dryer times, all the while increasing and decreasing the temperature; again mimicking the phases a device will go through in the real world. The aim of the test is to see how the materials in the phone will “weather” the conditions.

The video below shows the difference between a phone treated with the splash-proof (previously known as Aridion™) nano-coating, compared to an untreated device. The phones are going through the exact same test, and are periodically removed and photographed. 

What tends to happen is that as the temperature changes, water which may have entered the phone as innocent humidity, then condenses inside the phone, forming larger droplets. Now, not only do you have the oxidation of the metals, but you’re also in danger of electrochemical migration water damage, without ever getting your phone wet. 

Should I be worried?

Believe it or not, manufacturers are continuously looking for ways to make your phones more reliable. Motorola and Alcatel have already signed up to put the splash-proof coating on a range of devices before you buy them, so you don’t need to worry. We believe that as people continue to integrate the use of the mobile phone into every aspect of their life (including taking their phones in and out of humid conditions) then this trend from manufacturers will only increase. 

   

Waterproof and water repellent electronics...

On the back of the International CES and Mobile World Congress (MWC) tradeshows there has been an increased amount of discussion, and at times confusion on the difference between waterproof and water repellent electronics. In this post, we will shed more light and understanding on the subject, but before we begin, here is how each is defined:

• Waterproof: Impervious to water
• Water Repellent: Treated with a finish that is resistant but not impervious to penetration by water

Put simply, waterproof requires a physical barrier altering the device, water repellent does not change appearance and can be applied to any device.  

How do electronics become waterproof? 

The term waterproof is itself confusing as there are varying scales of 'waterproofness' that can be measured to determine how well electronics perform in and around water. This scale is known as the Ingress Protection Rating (IPX) and is based on a scale of 0-8 where 0 means it has no protection and 8 means it can handle continuous immersion in water. For example, an electronic device that has an IPX7 rating is protected against water submersion to a depth of 1m for no longer than 30mins. The level of water protection a device is capable of is usually highlighted by the manufacturer either on the device or in the manual.

For a smartphone to pass IPX6 and above, the devices physical appearance is normally compromized and this can be seen through the development of ruggedized handsets that feature protective rubber and plastic casings, as below:

Sonim XP3 waterproof phone

Fast forward to today and what was clear from the coverage at CES and MWC is that there is a strong desire for devices to be able to withstand water or other liquids. But unlike the above, the devices that are now appearing and claiming to be waterproof are not basic phones but instead are the latest smartphones on the market. What's more, these devices do not appear to have a protective case at all.

How are these new devices waterproof?

Well the answer is quite simple, gaskets and O-rings. Before water can reach the valuable internal components where all our data is stored there are barriers in place in the forms of gaskets and O-rings.  For quick reference a gasket is a mechanical seal which fills the space between two or more surfaces to prevent leaking while an O-ring is designed to be compressed between two parts creating a seal. While both these barriers stop water from penetrating inside the device they can still alter physical aspects of the device making them bulky as well as expensive to produce and purchase.

There is also another problem, these seals can be comprised by general use and over time the parts can move or be damaged should the device be dropped. If just one of these barriers were to break, water would then be able seep inside towards the circuit board and internal components, resulting in device failure and loss of data as the inside becomes exposed to water.

Why repellency over waterproof?

Firstly, we need to be clear what repellent means when talking about electronics and how it differs from waterproof. That is where Aridion™ comes in.

The key difference is that electronics treated with Aridion™ will still allow water to get inside. Does that mean the end of the devices life? Not necessarily, as Aridion™ molecularly bonds to both the inside and outside of the entire device ensuring that each and every exposed surface is coated. This means that any water that does come into contact will move away from the surface rather than sticking to the device and if water does get inside, the internal components are also treated, producing the same effect.

This type of protection allows the device to be created without having to compensate for a protective casing, gaskets or O-rings. What is important to remember however is that even though the water is repelled, the coating does not make the device waterproof as it is not designed to withstand submersion.

You can get a better idea of how the coating is applied and works in this video:

Aridion™ provides water protection by removing the buildup of corrosion. Corrosion occurs not just when a phone is submerged but in high humidity and moisture environments such as saunas, in the bathroom when having a shower or traveling through different temperatures. All these factors can lead to internal moisture buildup which over time can corrode the circuits. Aridion™ protects against this as it stops the water/moisture from sticking to and in between the components which would result in electrochemical migration. Electrochemical migration is the movement of metal ions between conductors and if this happens the device short circuits.

So what is the difference?

In the simplest terms, for a device to be waterproof it has to either be completely sealed and ruggedized (making them bulky) or alternatively it must have barriers in place which stops water from penetrating through. The disadvantage with that being these seals can break resulting in the device becoming susceptible to water and corrosion damage.

Water repellent does not mean waterproof but it does mean protection from splashes, spills, corrosion and water damage brought on by the scenarios mentioned earlier (humidty and moisture) as well as those 'caught out in the rain' moments we have all experianced.
If you would like to know more about Aridion™ technology and the benefits it offers you can here.

The following video which was filmed at MWC with our CTO Dr. Stephen Coulson visibly demonstrates the benefits that Aridion™ offers to electronics devices:

Aridion™ is applied during the manufacturing process and is already applied to over 9 million devices including the Motorola RAZR and XOOM 2.