The use of fire-resistant materials dates back centuries. A method of containing fire, including coating wood in vinegar and alum before encasing it in clay, was first used in China. It would then, many centuries later, be replicated by the Romans to protect their boats. And theatres in the UK used a similar method as recently as the 1500s to prevent stage curtains from setting alight. Alum is still used today in chemical and oil fire extinguishers. In more recent times, asbestos was commonly used as a fireproofing material, either alone or in combination with binders like cement. It was applied in different forms, such as sprayed coatings, pressed sheets, or as an additive in various products, including protective clothing fabrics and building materials. However, its use was banned in the UK in 1999 following evidence linking it to cancer. Asbestos was used from around the 1930s and was a particularly popular choice from the 1960s onwards, making it common in homes built or refurbished at this time. As a result, an entire industry dedicated to its removal and safe disposal has arisen. While asbestos is no longer deemed a suitable option, endothermic materials such as gypsum are still widely used. Fire doors, for example, use fire-resistant materials such as steel, gypsum, and aluminium. Fire door windows are made from borosilicate or ceramic glass, which provides higher fire resistance than regular glass.