The answer is usually between 3 to 5 days. But you may experience much longer or shorter protection from fogging. There are several factors that affect the duration of FogTech® and these are listed below along with some tips to lengthen the effect.

1. Application Method. FogTech® goes on differently than other anti-fogs. Specifically, you don't need to rub in our product to get a coating on the optics. A quick wipe will do. This application method guarantees an even coating of our active ingredients. So the key to longer protection is to follow the directions on the packaging exactly. Quickly wipe on a wet coat, back off and let dry. Tips: If you are using the bottle, put enough on the applicator to wet a spot the size of a 20 cent piece. More is definitely better than less. Don't unfold the towelette if using the packets. Do not continue to rub the coating especially after it dries. Make sure your optics are dry before applying.

2. Humidity, Perspiration and Respiration. The more moisture that contacts the surfaces of your optics, the shorter the anti-fog effect. This moisture can come from you, your skin, eyes and breath. It can also come from the humidity in the air. Last it can come from the equipment you are using, like steam cleaners. Because FogTech® is self spreading, it works hard to absorb this moisture. But eventually it can be overwhelmed and actually start to wash off the lens. Tips: If possible, let your optics dry out from time to time by taking them completely off. If you are using steam, you might want to use unvented goggles. Those will prevent extra moisture from coming in. FogTech® will handle the moisture from your face.

3. Time Between Uses. If you apply FogTech® to your optics and put them away for long periods, you will get less duration. You might also get some haziness as the coatings on the optics slowly cause FogTech® "bead up".

Tips: If possible, apply FogTech® right before using. Also you can apply a new coat right over the old one.

4. Type of Optics. Virtually all of your optics have a hardness coating on them to prevent scratches. The more 'hydrophobic' those coatings are, the shorter the duration of the anti-fog effect. (Highly hydrophobic surfaces cause water to bead up and even roll off the surface.) There are some coatings that are designed to resist water, oil, fingerprints and dirt that can also resist the application of FogTech®. We are happy to send samples of FogTech® so that you can try them on your particular lenses before you buy. Tips: Sprinkle a few drops of water on the lens. If the water quickly beads up and rolls of the lens, your duration could be shorter than average.

5. Covering Multiple Goggles, Masks or Glasses. One way to keep costs down is to coat as many articles as possible with the packets or the applicator. We have found that if you follow instructions, you should be able to coat 3 to 4 lenses with one packet or one applicator. Just do them at the same time. The carrier in FogTech® evaporates fairly quickly but you have a minute or two to work with it. Just make sure the applicator or towelette stays wet.

Tips: Gather the optics you want coated before you open the packet or ready the applicator. Ask others if they want their optics covered. As long the applicator is wet, you can cover up to 4 sets of lenses. We don't recommend trying to save FogTech® by sealing the applicators in a zip-lok bag or folding. They dry too quickly.