Waterproofing shoes can be beneficial in certain situations, such as hiking in wet conditions or working in a rainy environment. However, for everyday use, it may not be necessary for everyone. It ultimately depends on individual needs and preferences. Some people may find waterproofing to be a valuable feature, while others may not feel it is essential for their footwear. **

Leather shoes can become cracked after waterproofing because the process of waterproofing can sometimes dry out the natural oils in the leather, making it more prone to cracking. Additionally, some waterproofing products contain chemicals that can be harsh on the leather, leading to damage and cracking over time. It is important to use a high-quality leather conditioner in addition to waterproofing to keep the leather supple and prevent cracking. **

The duration of waterproofing on shoes can vary depending on factors such as the quality of the waterproofing treatment, the frequency of use, and the conditions the shoes are exposed to. Generally, waterproofing treatments can last anywhere from a few weeks to several months. It is recommended to reapply waterproofing treatments periodically, especially after heavy use or exposure to wet conditions, to maintain the effectiveness of the waterproofing. **

Leather shoes darken after waterproofing because the waterproofing product penetrates the leather and changes its appearance. The product creates a protective barrier on the surface of the leather, which can alter its color and texture. Additionally, the process of applying the waterproofing product can also cause the leather to darken as it absorbs the product. This is a natural reaction and should be expected when waterproofing leather shoes. **

To apply a new waterproofing membrane on top of an old bitumen waterproofing membrane, the surface of the old membrane should be thoroughly cleaned and prepared. Any loose debris, dirt, or old adhesive should be removed to ensure proper adhesion of the new membrane. Once the surface is clean, a primer should be applied to promote adhesion between the old and new membranes. Finally, the new waterproofing membrane can be installed according to the manufacturer's instructions, ensuring that it is properly sealed and bonded to the old membrane to provide effective waterproofing. **

McDonald's requires its employees to wear slip-resistant shoes to prevent accidents in the workplace. The company recommends shoes that meet the ASTM F2913-11 standard for slip resistance. Many popular brands such as Skechers, New Balance, and Dr. Scholl's offer slip-resistant shoes that are suitable for working at McDonald's. It's important for employees to check with their specific location for any additional requirements or recommendations. **

If shoes have blue stains after waterproofing them, it is possible that the waterproofing product used contained a dye or colorant that transferred onto the shoes. To address this issue, it is important to carefully read the instructions on the waterproofing product and ensure that it is suitable for the material of the shoes. If the stains persist, it may be necessary to try a different waterproofing product or seek professional help to remove the stains. **

If shoes have blue stains after waterproofing, it is possible that the waterproofing product used contained a dye that transferred onto the shoes. To address this issue, you can try gently wiping the stained areas with a damp cloth to see if the stains can be removed. If the stains persist, it may be necessary to seek professional help or use a stain remover specifically designed for the type of material your shoes are made of. It is also a good idea to carefully read the instructions on the waterproofing product before using it to prevent similar issues in the future. **