Regardless of how smart your electronics are, they need protection against the elements and daily handling, which comes in the form of an enclosure that provides mechanical and/or water protection. Some recent notable devices are the water-resistant Samsung Galaxy S8, iPhone X and wearables such as the Apple Watch Series 3 and most, if not all, modern smartwatches.
The term "water-resistant" does not necessarily mean that the device is "waterproof" or submergible, and the standard now used to measure the "waterproof-ness" of a device is known as the IP Code or Ingress Protection marking, which is based on ANSI-IEC60529 standards that classify and rate the degree of protection provided against intrusion such as dust particles, and water by mechanical casings and electrical enclosures. The standard is published by the International Electrotechnical Commission (IEC). The equivalent European standard is EN 60529.
IP codes are useful references to quantify a device’s water resistance, and mobile phone manufacturers have been marketing them to demonstrate the water resistance of their flagships. For example, Apple’s iPhone X is IP67 rated and the Samsung S8 has a rating of IP68. So what does IP68 or IP67 mean? Here’s a useful breakdown of those ratings.
Protection against Solids
The first numeral represents the level of protection against ingress of solids such as dust or sand, the ratings range from 0 to 6. The levels represent the size of particles that the device can keep out. The larger the particle, the lower the rating. As the device becomes increasingly capable of keeping out tiny particles, the rating gets higher.
Protection against liquids
Levels of ingress protection against liquids are 0-9K. These levels denote the movement, depth, and pressure of water the device is capable of withstanding. The higher the number, the greater the water resistance. In mobile technology, we generally see ratings 0-8, without any "K" designations, which denote increased water pressure.
Some manufacturers may go beyond the code itself and publish further specifications on the duration and depth of the water-resistant rating as part of differentiating in their marketing and this is usually done for adventure/outdoor types of devices such as fitness trackers.
An “X” put in place of the solid or liquid numeral denotes that the device is not rated for solid- or liquid- ingress protection. This is different from a complete lack of protection (which would be a zero). For example, an “IPX6” rating represents that the device is not rated for solid-ingress protection, but has level ‘6’ liquid-ingress protection.
In a nutshell, products that are designed to withstand environmental elements are given an IP rating. This will be the letter IP followed by two numbers. The first of these numbers indicates how well a device can withstand dust and solid objects, the second number indicates how well the device can withstand water. Any water-resistant phone that you buy will have an IP rating mentioned somewhere and depending on this rating will be able to withstand different movements, depths, and pressure of water. The most common IP water ratings for phones are 6, 7 and 8 (remember that we’re looking at the second number, so that’s IPX6, IPX7, and IPX8, where the X is a different number indicating dust resistance).
A device or smartphone with an IPX6 rating can withstand strong jets of water from any direction for 3 minutes (for example, a shower) but cannot be immersed in water whilst an IPX7 device can be immersed in water anywhere from 15cm to 1-m in depth for up to 30 minutes. An IPX8 rating means that the device can be immersed in water over 1 m in depth for an extended period.
What is IP69K?
The IP69K rating is the highest protection available and is a protection provision for high-temperature and high-pressure water which is prescribed by Germany’s standard DIN 40050-9 and is not a standard in IEC 60529. IP69K rating specifies a spray nozzle that is fed with 80°C water at 80 to 100 Bar and a flow rate of 14 to 16 L/min – making products with this certification ideal for use in conditions where equipment must be carefully sanitized such as devices in industries such as food processing, where hygiene and cleanliness are paramount, and equipment must be able to withstand rigorous high pressure, high-temperature washing procedures.
Water resistance does not apply to all liquids.
It is important to note that water resistance does not mean that the device is indestructible. For example, a common scenario is where a smartphone is accidentally thrown into the washing machine along with regular laundry. Whilst the water-resistant conditions of IP7 or IP8 may be met, the constant tumbling action may crack the waterproof O-ring or seal and the water resistance is lost. Another factor is the presence of chemicals. The IP rating specifies only resistance to water, not chemicals. Chlorine in swimming pools, corrosive seawater, acids present in liquid foods, surfactants in detergents, alkalis in household cleaners and alcohols in beer or wine could damage the device despite its water resistance.
Designing environmental protection or water resistance for devices is now more important than ever with IoT sensors or smart devices being placed into a new environment or for a new application where the device is subjected to environmental and weather conditions. By far the simplest and most common method of waterproofing is the addition of an O-ring between enclosure joints or barriers.
However, that approach may not be that straightforward when there are ports or connectors on the device, such as a power connector, a USB charging socket or a headphone socket. Or when the device emits a considerable amount of heat from its electronics that must be vented away, precluding the option to seal a device completely.
As each application varies, the design of new smart devices or IoT systems will need careful planning and engineering. Do contact us for queries on your next project!
To celebrate our 6th anniversary, we designed and trademarked a new logo to celebrate our past successes and symbolise the future of Thesis. At Thesis, we pride ourselves on helping shape our customers’ future. Our work helps our customers extend their technological advantage over the competition and opens up new growth opportunities. To illustrate this, […]
Here we show the waveform of a zero-voltage switching (ZVS) inductive heating circuit and the thermal profile in operation. A typical buck regulator DC-DC is challenging to design when there is a significant voltage difference between the input and the output voltages. A significant voltage difference typically increases switching losses and limits the device’s switching […]
In Thesis, we develop products using various MCUs – Cypress PSoC4/5/6, STM32, Nordic nRF, Arduino, and PIC. In the past, we did that because of various client requirements and/or outcomes from our in-depth engineering evaluation. However, we do it nowadays because we aim to make our product design as MCU agnostic as possible to circumvent […]