An environmental health officer (EHO; also known as a public health inspector) is responsible for carrying out measures for protecting public health, including administering and enforcing legislation related to environmental health and providing support to minimize health and safety hazards. EHOs keep water, food, air, land, facilities, and other environmental factors (factors external to a person) safe of health hazards, whether biological, chemical, or physical. They also address the related factors that impact behaviours. EHOs assess and control environmental factors that can potentially affect health, to prevent disease and create health-supportive environments. Environmental determinants of health play a major role in a community's overall health and well-being, and thus EHOs are essential in improving population health outcomes and reducing the burden of disease.

An environmental health practitioner (EHP) is trained to work to maintain a safe and healthy environment for the public. They are often required to have a degree and additional training, as well as be proficient in a variety of areas, including public health inspections, policy development, emergency response, disease prevention and control, and health promotion and education. EHPs may also be called EHOs and are responsible for preventing and addressing health risks, as well as educating the community on these issues.

EHPs have a deep understanding of fields such as microbiology, epidemiology, chemistry, toxicology, environmental science, and food science and are skilled in tracking and controlling communicable diseases and investigating environmental health incidents. They must also be familiar with relevant laws and regulations related to public health and safety. EHPs work with government agencies, local municipalities, businesses, and community groups to protect public health. Depending on the specific laws and definitions in their jurisdiction, they may also go by other titles, including environmental health specialist, public health inspector, and health official. Some past titles for this role include inspector of nuisances, sanitarian, and sanitary inspector.

Local, state, or federal health departments usually employ environmental health professionals to advise on and enforce public health standards. However, many are employed in the private sector, the military, and other third sector agencies such as charities and nongovernmental organisations.