Trisodium phosphate, or TSP, is a powerful cleaner for masonry, brick, stone and cement. It also cleans glazed ceramic tiles, although prolonged contact may damage the glaze. This chemical is often used to clean and prepare surfaces for painting.
TSP must be diluted with water prior to use and may be applied with a sprayer, brush or sponge. It is unsuitable for cleaning glass because it deposits residue. It also stains metal.
Gloves, long sleeves and safety glasses are essential for working with TSP because it causes chemical burns and severe eye irritation. It also harms plants, although spraying the leaves with water before and after applying TSP reduces the chance of serious damage.