PDAs for the Construction Business-How Tough is Enough?

For many years the personal digital assistant (PDA) was incredibly popular and effective for millions of consumers and office workers. Today, the PDA has nearly disappeared and has been replaced by the smartphone for those consumers. But when it comes to handheld devices that are used for business functions like rental car returns, field service tracking, asset management and more, the PDA is alive and well.  The only difference is that it’s usually a ruggedized device, and it’s typically called something else.

The DNA of PDA

Whether it’s called an “enterprise digital assistant,” a “mobile computer” or whatever, most of these specialized business devices will look familiar as a PDA, though appear a bit beefier. They are roughly the same size with color touch screen, keyboard, etc.  They typically run a flavor of the Windows Mobile operating system, a predecessor, Windows CE, or a flavor of the Linux OS.

There are numerous types of rugged PDAs that are suited for very different applications in industries like construction, manufacturing, retail and health care. Data capture and communication from the field or the factory is what these devices are all about. The main options center around input and communications, including:

• Keyboard (QWERTY or numeric)
• Touch screens
• Bar code scanners
• RFID tag readers
• Magnetic stripe (credit card) readers
• Infrared transceivers
• Bluetooth connectivity
• LAN (WiFi) connectivity
• Cellular data (Internet) connections
• Telephony (cellular or Internet VoIP)

Since these PDAs are expected to perform under all kinds of harsh conditions, nearly all of them have some level of ‘ruggedization.’

What Does Rugged Really Mean?

For most people, “rugged” refers to the durability of the PDA. What if your PDA sits in the rain for a few minutes? What if a foreman drops it onto a concrete floor? Will the dust kicked up by that truck dumping a load of soil get into the device? All of these things can happen on the jobsite.

There are four unofficial categories of equipment protection or ruggedization:

• Normal-commercial-grade products not typically facing rugged conditions
• Durable-more resistance to dropping, perhaps spill-proof keyboards
• Semi-Rugged-guards against difficult but not extreme environments (these devices undergo more testing and are rated with standards)
• Fully Rugged-safeguards conform to the most difficult conditions

The protections that are most commonly sought after by construction customers are:

• Surviving a fall-Fully rugged devices are expected to survive several drops of four feet or more onto hard surfaces, while semi-rugged devices will withstand fewer drops from lower heights. Durable devices will survive tip-over tests and short falls.
• Water resistance-Fully rugged devices can survive full immersion in water for short periods. Semi-rugged devices are often designed to resist rain, while durable devices might withstand splashes of liquids.
• Dust intrusion-Construction sites can expose PDAs to dust and sand that can cause movable parts to stick and malfunction. Semi-rugged and rugged devices are tested at various levels of airborne dust.
• High and low temperatures – Equipment can often sit in the sun and then be taken into an air-conditioned truck cab. The ability to operate at wide temperature ranges and survive the shock of temperature changes are part of testing for ruggedness.
• Vibration-A PDA sitting on an operating piece of construction equipment could experience problems like wire chafing, electrical shorts or shifting of buttons or display components. Vibration tests are part of the “torture testing” that ruggedized products go through.

Depending on the product and its intended use, there are other factors that are sometimes measured, including resistance to salt and fog, humidity, low pressure and vehicle crashes.

What to Look for in a Ruggedized PDA

The most common specification found in semi-rugged and rugged devices is the Ingress Protection (IP) standard for protection against water and dust. It’s a two-digit numeric rating where the first digit indicates the amount of protection against dust and the second digit against water. The most widely-used standards are IP54 and IP65. An IP54-rated product is protected against splashing water and has some dust protection, whereas an IP65 device is fully protected against dust and will survive jets of water similar to the product being hand washed. An IP68-rated product has the same dust protection but will survive total immersion in water.

The most rugged products are tested to stringent military standards. One of the most comprehensive is MIL-STD-810F. These products have been test against a battery of published design and testing criteria developed by the U.S. Department of Defense and the U.S. Army.

The Price of Ruggedness

Typical non-rugged consumer PDAs often ranged in price from $199 to $399. Part of the reason for their low cost is the very high production volume that they achieved. Today’s rugged PDAs sell in far fewer numbers and must be designed and tested to much higher standards of durability, so their costs are higher. Semi-rugged PDAs range from $550 for a product from Pharos up to the $1,200 range for products from manufacturers like Motorola and Intermec. Fully rugged PDAs that pass military standards are often priced over $2,000.

How Do You Choose?

Only you can decide what is the right PDA for your application, taking into account the conditions, how much the PDA will be used, the cost of the PDA and what a failure would cost you. The typical contractor is likely to need a semi-rugged product rated IP54 or higher. The price of more ruggedness is often not worth the additional cost.

A less expensive option is to take a normal or durable PDA and use a protective case like the OtterBox. For as little as $50, these cases add significant drop protection as well as water and dust resistance, but they can interfere with operations like bar code scanning or infrared communication.

While most consumers won’t see them, the PDA will be around a long time for business applications in industries like construction. The question that businesses are faced with is: “Do I purchase a normal commercial grade device that might need to be replaced soon, or do I pay the extra money up front for a ruggedized device that will have a longer life span?”

When you’re rolling out a technology application in the field, reliability and ease of use are what will make it successful. It’s worth the thought and the extra dollars up front to get the ruggedness that you need for your devices.