Tubes used for shipping are usually kept pretty dry. They're in a truck or inside a building for most of the time, and reputable shipping services, including the Post Office, do try to avoid damaging items in their care. But those mailing tubes still have to deal with rain when being carried to and from a building, and there is always the possibility that something in another package can leak (such as shipped medication, wine, and so on). The bad news is that you can't really stop a tube from being accidentally exposed to a liquid, but you can take steps that protect the items inside.

Thick Construction

One easy step is to get thick mailing tubes. Any suitable tube for shipping has to be rigid, and along with that usually comes a thicker material. However, some materials are merely reinforced while still being relatively thin. That means they might not bend easily, but liquid can soak through to the inside. Ensure the tube you use is thick. The outer surface might get soaked, but the moisture will have farther to travel before it hits the items inside the tube. And that gives people time to remove the tube from the area where the liquid is.

Tape, Mailing Labels, and Tube Ends

Even if liquid doesn't reach the inside of the tube through the sides, it can seep in through the ends -- or at least ruin the mailing label with the delivery address. Always place tape over the entire mailing label, extending over the sides, so that the print is fully covered. You can place two layers if you want. Also ensure the ends of the tube are securely taped, even if they have caps.

Plastic Tubes and the Weather Report

If you're shipping something to an area where the weather report calls for heavy rain, or an area that is known for its severe storms, you may want to use plastic tubing for that package. Cardboard suffices for most applications, but if heavy rain is a near certainty, making the jump to plastic can help. You'll still need to tape over the mailing label and ends, of course.

Cardboard mailing tubes are available in several sizes, shapes, and even colors, if you want to be festive. Finding the right one while considering the conditions the tube will be in is essential if you want to be sure that the contents won't suffer damage.