Final answer:
Hazard evaluations for a confined space must occur before entry and as needed to ensure safety, following OSHA's standards to protect against atmospheric and physical hazards.
Step-by-step explanation:
Hazard evaluation tests for the occupancy of a confined space must be conducted before entry and as needed throughout the occupancy to ensure that the environment remains safe. This is in line with OSHA's standards which require employers to ensure the safety of workers who enter confined spaces. Assessments must check for atmospheric dangers, potential physical hazards, and any other recognized serious hazards that could pose risks to the workers. These evaluations help to prevent exposure to harmful conditions and are a critical part of maintaining a safe work environment.