Purity levels refer to the degree of cleanliness or the absence of contaminants in a substance. This concept is commonly applied in various fields, such as chemistry, pharmaceuticals, and food production. For example, in the context of gold, purity is measured in karats, with 24 karats representing pure gold. In the realm of water, purity levels indicate the absence of harmful substances, such as bacteria or chemicals. Water is often tested for purity to ensure it is safe for consumption. Different standards exist for purity levels, depending on the intended use, such as drinking, industrial, or laboratory applications.