Good news for parents traveling by air with their children. The U.S. Transportation Security Administration (TSA) has announced that it is easing airport security screening procedures for children under the age of 12 years, and is also easing the rules for carrying liquid medications. But expect occasional exceptions to the new rules.

Here are the reasons for the new rules and the effects they will have on you and your children.

1. Children will no longer have to remove their shoes. Removing shoes during checkpoint screening was begun in 2001 when a terrorist tried to set off a bomb built into his shoe on a flight in December 2001. But few countries around the world adopted this requirement; countries in the European Union have never required travelers to remove their shoes. Apparently there are other methods to prevent such acts.

2. There will be fewer pat-downs of children. Screening procedures can be upsetting for young children; they are taught at an early age not to allow strangers to touch them. Screening is especially troubling for children with serious psychological and other behavioral issues.

3. Rules have been simplified for carrying liquids through security. This includes medications. You are now permitted to carry multiple liquids in quantities up to 3 oz. (100 ml) when placed in a quart (liter)-size, clear plastic, sealable bag. Medications in volumes larger than 3 oz. are permissible if placed separately and declared verbally or in writing to security personnel. A doctor’s letter explaining the medical need of the item is helpful but not essential. “Reasonable” quantities expedite checks.

4. New rules will not compromise safety. To reduce the number of pat-downs screeners will send children through metal detectors or the walk-through imaging machines multiple times to capture a clear picture, and use more explosive trace detection tools such as hand swabs.

5. New security devices are safe. There is no evidence that children will be harmed by metal detectors, even if they pass through the devices numerous times, or from hand swabs used to detect explosives.

6. Does full body screening violate children’s rights? Yes, say some child advocacy groups in the US and in Great Britain. These groups believe that screening devices that show full body images of naked children violate anti-pornography laws. Adults can refuse such screenings and accept pat-downs. Adults can make the same choice for their children.

7. Security checks of children will continue. According to counterterror experts, the psychological profile of terrorists does not rule out them using children - their own and others - in deadly missions, that children as young as ten years have been recruited to carry out missions, and that there is evidence that terrorists have planned to plant explosives in teddy bears and other children’s toys.

8. There will be exceptions to screening rules. And you will not be able to object if your child is asked to take off his or her shoes and is patted down, says the TSA. There will always be some unpredictability built into the system, and there will always be random checks even for groups that we are looking at differently, such as children. This is to help keep terrorists guessing.