UK authorities banned passengers from taking electronic items - such as iPods and notebook computers - as hand luggage on planes following the arrests of 21 people Thursday in connection with an alleged plot to blow up aircraft mid-flight en route to the US.

Other items, including liquids and food, are also banned, with few exceptions. The rules, available here, apply for all flights leaving or transferring through the UK, the British government said. The US government also banned liquids of all forms, including beverages and personal hygiene products, from being carried on to flights. All liquids must be placed in checked baggage. Additional information on heightened security measures in the U.S. can be found here and here.

Notebooks, iPods and mobile phones must be placed in checked baggage on flights out of the UK. Airline passengers have become accustomed to additional checks following the September 2001 terrorist attacks in the US. Airport security checks require that laptops must be removed from their cases and X-rayed. But the new security measures in the UK could mean an increased chance of theft or damage to laptops and devices that must be checked and not carried on.

From January through June of this year, US passengers filed nearly 1.8 million reports concerning mishandled baggage, according to US Department of Transportation statistics.

Protect your data

There are ways to reduce the risk of damage or the impact of a lost laptop, said Richard Starnes, a computer security expert and president of the UK branch of the worldwide Information Systems Security Association. Ideally, laptop users should already be following such guidelines, he said. The guidelines include:

Back up data: Enterprises may have a regular schedule for backing up data, but personal users may be less rigorous.

Passwords: Protecting a laptop with passwords is imperative.

Encryption: The data on a machine may be worth more to a thief or hacker than the hardware itself. High-profile losses of laptops have raised awareness about encryption, another way to ensure a lost laptop doesn't have other crushing consequences for a business.

Insurance: Data may be lost, but there will be compensation for the lost hardware. Airlines for domestic US flights usually limit their liability for baggage to $2,800 per passenger, according to the Department of Transportation. A top-grade laptop could exceed the limit.

Compensation for international flights is determined by an international agreement and is subject to currency fluctuations. As of February, baggage compensation for international trips was about a maximum of $1,400 per passenger, according to AirSafe.com, a website run by aviation expert Todd Curtis.

But a laptop faces other in-flight challenges, even if it isn't lost. Baggage handlers aren't kind to luggage, and notebook computers could be vulnerable to fatal bumps and tumbles.

Generally, the hard drives in laptops are designed to endure a 3-foot drop on concrete when turned off, Starnes said. A hard-shell case would offer more protection, at least while the laptop is in a baggage hold. The laptop could the be transferred back to a lighter bag after the journey, he said.