Which agency is responsible for setting guidelines for the sale, manufacture, and use of equipment and chemical ingredients?

The agency responsible for setting guidelines for the sale, manufacture, and use of equipment and chemical ingredients is the Environmental Protection Agency (EPA). The EPA's primary role is to protect human health and the environment by regulating harmful substances and ensuring that chemicals used are safe for consumers and the environment. This includes oversight of chemicals that might be used in various industries, including those relevant to nail technology, such as solvents and other hazardous materials.

The other agencies mentioned do play important roles in public health and safety but have different specific functions. The Food and Drug Administration (FDA) primarily regulates food, drugs, and cosmetics, ensuring that products are safe and effective for consumers. The Occupational Safety and Health Administration (OSHA) focuses on ensuring workplace safety and health, setting regulations and standards related to employee exposure to hazards. The Centers for Disease Control and Prevention (CDC) is mainly concerned with public health and disease prevention, rather than chemical regulation or guidelines for product manufacturing.

Understanding the roles of these different agencies helps clarify why the EPA is the appropriate choice for guidelines concerning equipment and chemical ingredients in various industries, including nail technology.