Solid sodium hydroxide or strong solutions produce immediate pain when they come in contact with any part of the body. Weak solutions may not produce pain for several hours, but serious burns can result even from weak solutions if they are not washed off quickly. Spilling sodium hydroxide over large areas of the skin or swallowing sodium hydroxide may cause shock and even death. Sodium hydroxide can break down proteins and generates heat when dissolving in water. Contact with sensitive tissues, such as the eyes, is particularly dangerous and can cause permanent damage or even blindness.

This alone is a reason to stick with what works! A soft wash roof cleaning done by a professional.