Hazardous waste sites must be characterized prior to general site entry to determine the hazards present at the site. When must this characterization occur?

• A. During initial entry
• B. Prior to general site entry
• C. After cleanup is completed
• D. At the end of the day

Answer: (B)

Before workers go into the main areas of a hazardous waste site, you need to identify what hazards are present. This characterization reveals contaminants, atmospheric hazards, unstable structures, and other risks, and it informs what protective measures are needed. With that information, you select appropriate PPE and respiratory protection, monitoring plans, engineering controls, decontamination procedures, and emergency response plans, and you set the entry conditions and work procedures. The characterization must be completed before general site entry so safety planning can be in place for all operations. Limited initial entry may occur to gather data, but it does not replace completing the characterization prior to broad access. It wouldn’t be done after cleanup or at the end of the day, since hazards and controls need to be known and applied throughout the work.