It looks like it’s going to be a LONG winter. During a recent shooting class I attended it started raining day one and by the middle of the second day it looked like a blizzard. Most of my fellow shooters were wearing waterproof breathable outerwear and several began to feel clammy and then damp the longer each day progressed. A couple of guys were wearing issue Gen I ECWCS parkas. Probably not the best garment available as Gore long ago decided that the basic design could not meet their “Guaranteed to Keep You Dry” standards. Of course these jackets were old. More than anything, they needed some maintenance.

The key to any modern outerwear is its Durable Water Repellent (DWR). There are quite a few treatments available and different manufacturers have their favorites but they are usually are based on flouropolymers. These are PTFE molecules that are applied to the surface and cured at high heat to make them adhere better and increase performance and have a fluorine atom at one end which is highly hydrophobic. Heat causes them to align themselves with their flourines exposed. Water tries to move away from the flourines resulting in beading. This allows the water to roll off without wetting the fabric. Interestingly, Quarpel (Quartermaster Repellent) was one of the first DWRs and used to treat field jackets and other military clothing items.

Since most of us can’t run out and purchase a new jacket every time this happens I thought it would be a good idea to share a few tips with you that will not only revitalize your garment’s DWR treatment but also extend the life of your clothing.

DWR treatments work best when they are clean. I realize this seems counter to what you think is right since a DWR generally lasts about 25 washings and tactical garments get quite a beating in the field but you need to wash your clothing. The first thing is to avoid using liquid detergents as well as fabric softeners. Additionally, avoid optical brighteners as they are not good for DWR or IR treatments. There are wash in treatments you can purchase as well as spray on options to help renew your clothing’s DWR. However, wash in treatments may affect the breathability of your membrane. One of the best spray solutions available is Revivex from McNett and it is what I have used in the past. It also serves as a stain repellent. Revivex can also be applied to garments that never had DWR in the first place so if you have hunting or field clothing that you find yourself wearing in inclement weather regularly you may want to give it a once over. If you use a spray treatment be sure to evenly coat your garment while it is still damp after washing and to pay special attention to any seams.

There are two additional ways you can put some life back into your DWR. One is to put the garment in a conventional dryer on warm and the other is to iron it on low heat. If water fails to bead up on the surface of your garment you will need to retreat.

No matter which method you choose, proper maintenance of your foul weather clothing’s DWR will help keep you warm and dry and extend the life of your equipment.

Researchers at UC Berkely have created energy-scavenging nanofibers from organic polyvinylidene fluoride, or PVDF, which makes them flexible and relatively easy and cheap to manufacture. They work by harvesting energy from ordinary body movements. These nano-sized generators have “piezoelectric” properties that allow them to convert the energy created through mechanical stress, stretches and twists into electricity and who twist and stretches more than a Soldier in the field? The nanogenerators have diameters as small as 500 nanometers, or about 100 times thinner than a human hair and one-tenth the width of common cloth fibers. Additionallym the researchers repeatedly tugged and tweaked the nanofibers, generating electrical outputs ranging from 5 to 30 millivolts and 0.5 to 3 nanoamps. Such performance would make them well suited for use in a combat uniform.

We continue to see the development of these piezoelectric technologies that harness energy from common tasks. Some are integrated directly into the clothing and footwear and others are appliques designed to be added and removed from equipment as needed. Currently, the nanofibers features in this article are averaging about 12/5 percent efficiency but one day much of power a Soldier needs for his equipment may come from energy harvested as he conducts common tasks. Oh the possibilities.