Which U.S. federal government agency sets policy and regulations for protection of the environment?

The Environmental Protection Agency (EPA) is the U.S. federal government agency responsible for setting policies and regulations aimed at protecting the environment and human health. Established in response to growing concerns about pollution in the late 1960s and early 1970s, the EPA's primary function is to enforce federal legislation regarding air and water quality, waste management, and chemical safety, among other environmental concerns.

The EPA develops and enforces regulations based on laws passed by Congress, carrying out tasks such as monitoring environmental conditions, conducting research, and working with state and local governments to ensure compliance with environmental regulations. Its work is critical in safeguarding natural resources and public health, ensuring that environmental standards are maintained and improved across the nation.

In contrast, the other agencies listed play different roles. The Department of Defense focuses primarily on national security and military affairs. The National Institute of Standards and Technology is involved in developing measurement standards and promoting innovation. The National Institute for Occupational Safety and Health is dedicated to ensuring workplace safety and health. While all these agencies contribute to various aspects of public policy, it is the EPA that specifically focuses on environmental protection.