• Structural security: Validate the structural integrity of the building or facility before anyone re-enters.
• Re-entry: Contact the proper government agencies for approval to resume occupancy of the building. Do not enter a facility unless the proper clearances are in hand.
• Clean-up: Clean-up and business resumption should be conducted in a safe and healthful manner. Provide personal protective gear, such as eyewear, gloves, and dust/masks/respirators for cleaning, and training in its proper use.
• Air quality: Make sure the atmosphere in the workplace environment is tested for asbestos and other chemical or toxic agents; then perform any necessary remediation.
• Ventilation: Check vents to ensure that water heaters and gas furnaces are clear and operable. Dust and debris can stop or impede airflow, decreasing its quality and healthfulness. Safely start up heating, ventilation, and air conditioning (HVAC) systems, including prior inspection of lines, before energizing and pressurizing the systems. Re-test the systems after inspection or have a qualified specialist do so. Blow cold air through HVAC systems first, rather than warm air, to help prevent the growth of mold in duct systems.
• Interior/exterior exposures: Be sure that no interior wall or ceiling materials are in danger of falling. If such exposures do exist, the space is not ready for occupancy. Check for cracked windows and outside building materials that could fall onto pedestrians.
• Fire protection equipment: Clean and test all fire and smoke alarms before allowing occupancy of the building. If these are wired into other systems, be sure that they remain compatible and in good working order. Inspect fire- suppression systems.
• Electrical safety: Check electrical systems, computer cables, and telecommunications equipment to be sure there are no electrical hazards. Wiring inspections should be conducted from the outside so that wiring and connections are not in danger of shorting out because of water damage from rain or firefighting.
• Power checks: If there is no access to electricity on the site, do not use fueled generators or heaters indoors. Make sure there are no gas and sewer leaks in the facility. Coordinate with local utilities to get power restored.
• Health/sanitation: Inspect and test general sanitation systems to guard against potential employee exposure to toxic agents. Any unused food items should be discarded.
• Solid/hazardous waste removal: Broken glass, debris, or other materials with cutting edges should be safely disposed of before regular collection to avoid creating larger hazards for employees and the public. Evaluate waste disposal needs before beginning clean-up operations.
• Machine inspections: Inspect the condition of drain, fill, plumbing, and hydraulic lines on all processes and equipment. Consider having plumbing lines evaluated and tested to detect any hazardous gases.
• Surfaces: Check flooring surfaces for slip, trip, and fall hazards.

Make sure your emergency plan is up to date, including designation of a place for employees to gather once out of the building, and a phone number/website they should contact so everyone can be accounted for. The aftermath of an incident is, of course, one of the times your overall emergency plan should be assessed. Ideally, such reviews occur regularly and proactively, rather than because the plan has been put to the test in an actual disaster.