The removal of soiling from a building can be achieved using water, chemicals, poultices, lasers, and also mechanical cleaning methods. Mechanical cleaning requires the use of force using hand-held tools such as brushes, sponges, scalpels etc. or with equipment such as vacuums, or dry air-abrasion. Mechanical cleaning can be low-impact, and is often used where water or chemicals are not suitable. However, stone can easily, immediately and permanently be damaged by mechanical cleaning.
Abrasive cleaning systems direct particles onto soiled masonry in a stream of compressed air of between 1.5 and c.7bar. The systems work by Continue reading