The UV protection is only recommended if the area will be exposed to sunlight on a regular basis. It will not lose it's effectiveness, but will turn into a brown color. Believe the advice about wearing gloves and wear a long sleeve t-shirt, too. The stuff took days for it to wear off my skin. Throw away the cheap bristle brush, as the bristles fall off and end up in your work. Instead buy sponge brushes that are just as easily disposable and provide a smoother looking finish.