Gloves that are chemical- and heat-resistant are worn when transferring chemicals, working on hot pumps and valves, and when working with hot or hazardous chemicals. Chemical-resistant gloves are made of rubber polymers that withstand exposure to acids, bases, solvents, and other chemicals. Heat-rated gloves have been tested to CE EN 407 or ANSI standards. The rating determines the temperature at which a worker will begin to feel a burn when handling an item. The time to feel a burn is affected by temperature, object weight, and length of time the object is held. Higher numbers (5) indicate that the glove provides greater protection than lower numbers (1). Gloves with higher levels of protection are generally thicker than gloves with lower levels of protection. Thinner gloves have a better sense of touch and less chemical resistance than thicker gloves.