The advantage of an impregnating agent, based on waxes, is that the wax is UV inert. When exposed to UV rays, after a few years the classic systems work less and less. On the other hand, lab tests have shown that after six years, surfaces treated with wax emulsions still contained sufficient wax particles, which continue to have a water and dirt repellent effect. Our WTCB report clearly shows that certain surfaces could be tested up to four times longer.