Cross-contamination is the transfer of unwanted material from one location, surface or item to another.
What this means at your property
Shoes, tools or belongings moved through a cleanup area can carry residue into an otherwise unaffected room. A work plan should consider traffic routes and handling of equipment as well as the surface being cleaned.
Can occupants move items out before the crew arrives?
Ask first which items and routes are appropriate. Record priorities for belongings that need access, and agree on how items leaving the work zone will be identified and handled. Moving everything quickly can complicate the cleanup boundary.