Final answer:
In sewers and utility tunnels, one should use written safety procedures that are approved and enforced by OSHA to ensure worker safety.
Step-by-step explanation:
In sewers and utility tunnels where isolation is not possible, it is important to use written safety procedures that are approved and enforced by the Occupational Safety and Health Administration (OSHA). OSHA is a government agency responsible for ensuring occupational safety and health in workplaces. They have established standards and regulations to protect workers from various hazards.
Using written safety procedures helps to ensure that workers are aware of and follow the necessary safety precautions to prevent accidents and injuries. These procedures outline the specific steps and guidelines that workers should adhere to when working in hazardous environments, such as sewers and utility tunnels.
By following OSHA-approved safety procedures, workers can reduce the risks associated with working in such environments and promote a safer work environment overall.