This OSHA instruction revises CPL 02-02-059, issued April 24, 1998. This instruction updates enforcement procedures for compliance officers who need to conduct inspections of emergency response operations. It defines additional terms and expands on training requirements for emergency responders and other groups such as skilled support personnel. New guidance is provided on how HAZWOPER may apply to unique events such as terrorist attacks and addresses OSHA's role under the National Response Plan. This instruction will assist other Federal, State, and local personnel who have responsibilities under incident command systems and will assist in emergency response operations. This instruction updates policy and provides clarification on the following issues: HAZWOPER's application to a terrorist incident response involving chemical, biological, radiological, or nuclear materials. OSHA's relationship with Homeland Security Presidential Directive (HSPD-5), including discussion addressing the National Response Plan (NRP), the Worker Safety and Health Support Annex, and the National Incident Management System (NIMS). OSHA's National Emergency Management Plan (NEMP) and Regional Emergency Management Plans (REMPs). Definition of "First Receivers." OSHA's "Best Practices for Hospital-Based First Receivers of Victims from Mass Casualty Incidents Involving the Release of Hazardous Substances." Shelter-in-Place. Damaged packages during shipping. Skilled Support Personnel. Emergency responder training levels. Medical Surveillance for emergency responders. Computer-based training. Updates to citation guidelines.