Example 1:  Consider the water tap.  The in-built locking mechanism allows the owner to prevent its unauthorized usage. 

Example 2: Take a look at the metal enclosure built around the machine, which provides physical security and prevents unauthorized access, usage or tampering of the machine.

Example 3: The login or sign-in mechanism built in a software product provides security against its unauthorized access or usage.

Example 4: Anti-virus software tools provide security against unauthorized software, malware or virus from accessing, stealing, destroying or manipulating data, or infecting operating system or software applications installed on a computing system.

Availability is expressed as a percentage and is computed by the following formula:

Availability % = ((Total duration - Sum of individual downtimes during the entire duration) / Total duration) * 100

In a month, if a product has a downtime 1 hour on Day-3, 2.5 hours on Day-13, and 1.5 hours on Day-29, then, its cumulative downtime during the entire month is 5 hours.  The availability of the product during this month is then computed as: (((30 days * 24 hours) - 5 hours) / (30 * 24)) * 100 = 99.30 %.  The higher the availability of a product, the lesser the chance of it failing, breaking down or becoming in-operational.   However, achieving higher availability comes at a high cost.  So, a product designer has to balance the availability of the product with the cost involved in building and operating it.

Example 1:  Consider the case of the AC-powered vacuum cleaner we discussed earlier as part of the Performance attribute.  This is a portable hand-held vacuum cleaner suitable for cleaning table-tops, beds, sofas and other furniture.  The vacuum cleaner can be operated for a maximum of 15 minutes in one go.  If used for more than 15 minutes, the motor inside the cleaner heats up and the chances of the cleaner getting damaged increases. So, it is advisable to limit its operation to 15 minutes at a stretch, and allow the cleaner to cool down for the next 5 minutes before using it again.  So, effectively, in an hour's duration, the vacuum cleaner's availability is a maximum of 45 minutes with a downtime of 15 minutes.  This translates to an availability of 75% only.

Example 2: Consider a mobile network infrastructure similar to that of Airtel, Vodafone or Reliance Jio.  The availability of the end-to-end mobile infrastructure is very crucial.  Even a few minutes of downtime means all ongoing mobile calls will drop and no new calls can be made by users.  This can mean a loss of several crores of rupees to the service provider. As such, mobile network infrastructure are typically designed for very high availability (of the order of 99.999% or higher) with a cumulative downtime of not more than a few minutes or hours in an entire year.

Example 1: Netflix personalizes movies recommendations to you based on the type and genre of movies you have watched on Netflix in the past.  

Example 2: Google Nest thermostat has the ability to automatically personalize your home temperature by learning from your past preferences.

Example 3: Hector, the smart connected car from Morrison Garages (MG) allows you to customize your driving preferences.  The car can even welcome you with a personalized greeting as you approach the car. 

Example 4: Nutella is a brand of sweetened hazelnut cocoa spread which is popular with children. The company that makes Nutella allows its customers to personalize the jar by having their name printed on the jar and have it shipped to them.  

Example 1: A self-driving car can be considered a smart vehicle that uses several sensors, microprocessors and software algorithms to determine road conditions in real-time and drive the vehicle autonomously.  Such cars are already under road trials.  Soon, they may be a reality on city roads.

Example 2: A smart refrigerator is one which can identify what items in the refrigerator need replenishment (such as milk, eggs, vegetables, etc.)  and place order with the nearest grocery store automatically.

Example 3: The Google Nest thermostat is a smart product that can automatically adjust the temperature in your home based on your preferences and past settings.

Example 4: Roomba is a smart robotic vacuum cleaner that uses sensors, robotics, artificial intelligence and wireless technologies to clean floors in homes autonomously.

Example 1: A software program is said to be compatible with Windows operating system (OS) if it can be run on all Windows based computers.

Example 2: A printer and a computer are said to be compatible if they can be connected to each other through a common coupling mechanism to facilitate sharing of data between the two.

Example 3:  A bolt and a nut are compatible with each other if the nut can be fastened to the bolt tightly and held in place.

Example 4: A bulb and a bulb-holder are set to be compatible with each other if the bulb can be affixed to the bulb-holder making proper electrical contact between the two.

Example 1: Laptops and mobile phones that implement the universal serial bus (USB) standard can inter-operate with each other through the USB cable to exchange information.  

Example 2: Smartphones and television sets that implement the WiFi wireless networking standard can interoperate with each other.  This makes it possible to remotely control the TV from a smartphone.  One can also play videos, music or cast mobile screen on the TV screen via the Wifi interface.

Example 3:  Two mobile phones that implement the bluetooth standard can inter-operate with each other. This makes it possible to exchange photos, videos, contacts and apps between them via the bluetooth interface.

Example 4: Two ore more computers can inter-operate with each other using standard web protocols such as HTTP.

Example 1: Size and shape of electrical plugs and sockets are generally standardized within a country.  In India, Bureau of Indian Standards (BIS) has specified the standards to be used for plugs and sockets for electrical appliances made in India.  This ensures that any electrical appliance that needs power from the main power supply can easily plug into the wall socket.  If the dimensions of the plug and the socket were to be different, they would not fit into each other, and you would have trouble powering on the electrical appliance.  

Example 2:  All Internet web-browsers implement HTTP, the standard web protocol defined by Word Wide Web Consortium.  In addition, all web browsers support HTML, a web page rendering standard.  This enables any web-page to be displayed on any web-browser in identical fashion irrespective of the web-browser, operating system or computer.

Example 3: Any product supporting WiFi connectivity has to comply with the IEEE 802.11.x standard from Institute of Electrical and Electronics Engineers (IEEE). 

Example 4: Vehicle tyre manufacturers comply with standards defined by International Standards Organization (ISO). These standards provide specifications for tyres of different sizes and vehicle types including cycles, moped, motorcycles, cars, trucks, buses, tractors, etc.  

Example 1: Bharat Stage Emission Standards (BSES) are emission standards instituted by the Government of India to regulate the emission of air pollutants from internal combustion engines and spark-ignition engines & equipment, including motor vehicles.   BS-VI emission standards came into effect from April 2020 which requires all vehicle manufacturers in India to comply with the new emission regulations.

Example 2: All medical devices and equipment sold in India are regulated by the standards published and enforced by the Central Drug Standards Control Organization (CDSCO) in India. 

Example 3: To promote the safety and the right usage of electrical equipment, the Bureau of Indian Standards (BIS) has formulated rules and regulations which encompass safety, ease of use and adaptability, simplicity of technology, value for money and energy efficiency of electrical products.  It is mandatory for product manufacturers to comply with these regulations.

Example 4: For manufacturers who want to market products with built-in wireless technologies in the Indian market, MCITT certification is essential.  

1. The chair is comfortable to use.

2. The chair is stable and therefore safe.

3. The chair allows the user to move freely.

4. The chair uses waterproof materials and are easy to clean.

5. The chair is made of materials with the right resistance, in order to avoid breakage while in use.

6. Parts of the chair are removable and replaceable as part of a normal maintenance activity.  

7. The chair has dimensions that are suitable for the majority of the population (> 95%) to use.

8. The chair is equipped with a mechanism that allows the height of the seat to be adjusted to different heights, regardless of the back rest. 

9. The back rest of the chair is designed in such a way as to provide adequate support for the back.  The chair may optionally provide additional support for the lumbar-sacral area. 

10. The chair has rounded edges to avoid the risk of accidents and the ends of the hollow edges are always plugged. 

11. The chair is to be equipped with a stable five-spoke base so that it reduces the risk of accidental slipping and tipping of the chair. 

12. The chair is equipped with adjustment mechanisms that allows it to be adapted to the physicality of the user: adjusting the height of the seat, the inclination and height of the backrest, the height of any headrest and the height of the armrests. 

13. The chair has a rotation system on its own axis, which allows the worker to turn 360° without having to stand up. 

14. The chair uses fire-retardant or anti-inflammable materials to prevent it from catching fire.  

15. The chair makes use of anti-microbial textiles to prevent allergies or rashes to the user.