Surprises at Security: You Can Bring This But Don't Bring That

— -- I was recently asked why so many people try to bring guns through airport security; the Transportation Security Administration recently confiscated 35 of them in a single week -- including 29 loaded weapons.

Not to make light of this, but the vast majority of passengers simply don't do it and those who do usually say they "forgot." For some perspective on the number, consider that in 2013 alone, U.S. airlines carried nearly 650 million passengers.

But even a few incidents can slow down security lines for everyone -- as does the far more common occurrence of trying to bring a water bottle through the checkpoint.

Here's an idea: Keep the line moving, especially during the holidays, by seeing what you can and can't bring through security before you fly. Some of these items may surprise you.

Items Permitted Through Security

A sampling of what is allowed on your person or in a carry-on bag. Some items are wacky, some are surprising, some might save you time and trouble.

• Bear repellent: This is approved unless its chemical makeup is over "2% active ingredient"; unfortunately, most bear repellents exceed this.

• Scissors: Blades must be 4 inches long or less.

• Wrenches: 7 inches long or less.

• Screwdrivers: 7 inches long or less.

• Fishing poles: Just make sure it fits in your carry-on.

• Knitting needles: No size limits.

• Valuables: Diamonds and rare coins are fine but the TSA recommends you request a private screening. I recommend you leave them at home.

• Ice skates: Yes, but no triple axels in the aisles, please.

• Tennis racket: No problem but do not be tempted to use it during any reclining seat disputes.

• Life vests with small compressed gas cartridges: For those who presumably worry their plane might run short.

• Snow globes: Must have no more than 3.4 ounces of liquid inside, so a snow globe the size of a tennis ball will be approved.

What's surprising is how many of these items could theoretically be used as weapons but apparently the TSA feels length limitations and passenger common sense will do the trick.

Items Forbidden Through Security

There should be no need to list items like explosives or hand grenades or fireworks because they're obviously not allowed through security (or in checked-bags), yet people bring such items to the airport week after week. Use your common sense and when in doubt, check the TSA website.

• Guns: Not allowed in carry-ons but may be allowed in checked-bags with proper paperwork depending on the airline.

• Jar of peanut butter: Illegal items can be hidden inside; a jar was used in the past to stash marijuana. By the way, while the TSA doesn't actively search for drugs and other illegal substances, if they find anything they are obligated to call in local law enforcement.

• Replicas of hand grenades or other weapons: Officers may not be able to tell the difference between a fake and the real thing and don't have time to investigate.

• Pepper spray or mace for personal use: Okay, but only in checked-bags.

• Golf clubs: I know, I know, rackets and skates, no problem, but golf bags must be checked.

• Snow globes: As noted, tennis ball-sized ones are okay but only if you can fit the souvenir in a quart-size zip bag along with your toiletries.

Got all that? If you still have questions, the TSA has an app called, "Can I bring my ... through security" and you can find that here. If you still aren't sure, leave it home.