Sheltering in Place Published July 30, 2014 By Michael R. Hackler Command Emergency Manager, HQ AMC/A7XR TMF Fall 2014 -- Sheltering in Place By Command Emergency Manager, HQ AMC/A7XR The release of airborne hazardous materials (HAZMAT) is a real threat to our personnel. This threat may be accidental or intentional releases from transportation modes, storage facilities, day-to-day use, or terrorist use of weapons of mass destruction (WMD). The hazards we are most concerned with are those heavier than air. Lighter-than-air HAZMAT could pose a localized threat from release but dissipates quickly into the atmosphere. As soon as a release occurs, an airborne plume will travel with the wind, following the contours of the landscape. We are racing the clock from the moment of release until it reaches your building. By the time it takes emergency responders to respond, check out the situation, and initiate warning and notification, the airborne hazard will probably be at your building. Once the hazard reaches your building, it may enter through doors, windows, and the building's heating, ventilation, and air conditioning (HVAC) system. Our job as leaders is to protect our men and women and to continue or recover the mission. For years, the easiest and least expensive method to protect personnel was evacuation. It uses a basic principle of getting away from the hazard. Concerns arise when there is an airborne hazard in the area as we try to evacuate because our personnel could walk into an airborne plume of HAZMAT. Use common sense and available information to assess the situation and determine if there is immediate danger. If you see large amounts of debris in the air, or if local authorities say the air is badly contaminated, you may want to shelter in place. Sheltering in place (SIP) protects personnel by using a building's indoor atmosphere to temporarily separate people from an airborne hazard. Studies have found that facilities provide substantial protection if air entering the building is filtered, reduced, or temporarily interrupted. Interrupting the airflow is the basic principle applied with SIP. If done properly, SIP provides substantial short-term (two hours or less) protection from concentrations high enough to cause injury. Personnel are still in the danger area but are protected by the barrier created by the facility and its indoor atmosphere. The amount of protection provided by SIP varies with the air tightness of the facility and the length of time the building is exposed to a hazardous plume. Modern energy efficient buildings are better candidates for SIP than older facilities. SIP should not be used when the building's structural integrity has been damaged, such as when part of the building has collapsed after an explosion. Achilles Heel HVAC systems are the Achilles' heel of SIP. Outside air is drawn in and tempered to provide a comfortable indoor environment. When left in operation, HVAC systems will pull in air, equally distributing it throughout the building. You must have the capability to turn off HVAC immediately whenever personnel are present in order to make SIP a viable option. These systems may be centrally managed or have individual controls for each system within a building. Larger buildings may have 10 or more individual systems, each requiring steps to shut down. Your facility manager or local civil engineers should be able to assist if you have questions. Certain communications systems depend on air conditioning, and shutting down HVAC may cause damage or loss of mission capability. Commanders must decide if the mission must continue at a greater risk to occupants or if it will be transferred to an alternate location. Identify SIP Rooms Determine if SIP is feasible for the building. Modern energy efficient buildings provide the most protection once the HVAC systems are turned off. Older wooden or steel-sided buildings should be carefully checked. Smaller interior rooms may be best suited in these buildings. Determine maximum number of personnel that require SIP protection--not only how many are assigned but also how many are routinely in the area. This number is used for planning a SIP room (or rooms). Identify potential SIP rooms. Since no room will be ideal, units must make the best decision based on the building. Desired characteristics for SIP rooms are those on upper floors, away from outside walls with few or no windows, and in a central location for all occupants. Communications capabilities such as a telephone (minimum), computer with email access, and cable TV are highly useful. Select interior rooms above the ground floor, with the fewest windows or vents. The rooms should have adequate space for everyone to be able to sit. Avoid overcrowding by selecting several rooms if necessary. Large storage closets, utility rooms, pantries, copy and conference rooms without exterior windows will work well. Avoid selecting a room with mechanical equipment like ventilation blowers or pipes, because this equipment may not be able to be sealed from the outdoors. Use 10 square feet per person to calculate the maximum occupancy of SIP rooms with a standard ceiling height. The breathable air in this type of room will easily last for two hours; however, buildup of heat and carbon dioxide may cause some people to experience headaches. People with poor health may become casualties to the heat or carbon dioxide buildup--or just from the tight quarters. Consider adding SIP rooms if you're close to the maximum occupancy. Put SIP Kits Together SIP kits contain inexpensive and easy-to-use products to "seal" yourself inside, thereby keeping hazards outside. Suggested contents include: Instructions on how to implement SIP in the room and whom to notify Plastic sheeting (6 mil minimum) cut to cover HVAC supply and return vents Duct tape (10 mil minimum) to seal doors and windows and to secure the plastic sheeting Radio to listen for updates on the situation Flashlights in case the power goes out First aid kit Shelter In Place door signs (one per exterior door) Exercise SIP Conduct SIP practices on a regular basis at different times of the year. Conduct some drills when people have opened windows and doors for ventilation. If the facility operates at night or on weekends, conduct drills at those times, too. Whenever possible, participate in installation-wide exercises. The most important thing is to get feedback from participants, and incorporate the lessons learned into your plan.