BUILDING DESIGN FOR HOMELAND SECURITY Unit VII Chemical, Biological, and Radiological (CBR) Measures Unit Objectives Explain the five possible protective actions for a building and its occupants. Compare filtration and collection mechanisms and applicability to the particles present in chemical, biological, and radiological agents. Explain the key issues with CBR detection. Identify the indicators of CBR contamination. Unit VII: CBR Measures Units I-V discussed Assessments Đ Risk. Units VI and VII explain Blast and CBR Weapons and effects. Units VIII and IX demonstrate techniques for site layout and building design to counter or mitigate manmade threats. CBR Measures: An Overview FEMA 426, Chapter 5 is based on best practices for safeguarding building occupants from CBR threats. This module is organized into four sections : . Ą Protective Actions for Buildings and Occupants . Ą Air Filtration and Cleaning Principles and Technology . Ą CBR Detection and Technology . Ą Non-Technology CBR Contamination Indications What is the CBR Threat? POTENTIAL IMPACT PROBABILITY/LIKELIHOOD Why Would Terrorists Use CBR? . _ Available and relatively easy to manufacture . _ Large amounts not needed in an enclosed space . _ Difficult to recognize . _ Easily spread over large areas . _ Strong psychological impact . _ Overwhelms resources CBR Sources . Ą Laboratory/commercial . Ą Industrial facilities .Ą Foreign military sources . Ą At least 25 countries possess chemical agents or weapons . Ą 10 countries are suspected to possess biological agents or weapons . Ą Medical/university research facilities . Ą Nuclear facilities . Ą Home production Limitations of CBR Materials . Ą Effective dissemination is difficult. . Ą Delayed effects can detract from impact. . Ą Counterproductive to terroristsŐ support. . Ą Potentially hazardous to the terrorist. . Ą Development and use require skill. Chemical Agents: Characteristics and Behavior . Ą Generally liquid (when containerized) . Ą Normally disseminated as aerosol or gas . Ą Present both a respiratory and skin contact hazard . Ą May be detectable by the senses (especially smell) . Ą Influenced by weather conditions Classes of Chemical Agents Comparative Toxicity How Much Sarin Does it Take? LD50 amounts for one minute exposure to sarin liquid BUILDING DESIGN FOR HOMELAND SECURITY Unit VII-14 Chemical Agents Key Points . Ą Chemical agents are supertoxic . Ą Relative toxicity: industrial chemicals < mustard < nerve . Ą Normal states are as a liquid or a vapor . Ą Inhalation hazard is of greatest concern Classes of Biological Agents Bacteria Viruses Toxins Note: There are numerous naturally-occurring toxins. For our purposes, we will group them into two categories. BUILDING DESIGN FOR HOMELAND SECURITY Unit VII-20 Biological Agents Key Points Onset of symptoms Contagious Signs and symptoms Protection Treatment Common Radiation Exposures Chronic Acute Health Hazards in an Incident . Ą Exposure to radiation source (external) . Ą Contamination (possible internal and/or external) Protection from Radiation Exposure TimeDistanceShiel ding CBR Detection Radiological Chemical Biological ? Chemical Incident Indicators (1) Chemical Incident Indicators (2) Biological Incident Indicators Radiological Incident Indicators CBR Protection Strategies Protective Actions: . Ą Evacuation . Ą Sheltering in Place . Ą Personal Protective Equipment . Ą Air Filtration and Pressurization . Ą Exhausting and Purging Evacuation Most common protective action In most cases, existing plans for fire evacuation apply Ą Assembly should be upwind and at least 1,000 feet away BUILDING DESIGN FOR HOMELAND SECURITY Unit VII-33 Sheltering in Place (1) A building can provide substantial protection against agents released outside if the flow of fresh air is halted or significantly reduced The amount of protection varies with: . _ How tight the building is . _ Duration of exposure . _ Purging or period of occupancy . _ Natural filtering Sheltering in Place (2) . Ą Sheltering Plan should include: . Ą Identifying all HVAC equipmentto be deactivated . Ą Identify cracks, seams, andjoints to be temporarily sealed . Ą Prepositioning supplies . Ą Identify safe rooms . Ą Identify procedures for purging . Ą Identify procedures for voluntary occupant participation Personal Protective Equipment Air Filtration and Cleaning Two Types of Collection Systems: Particulate air filtration . Ą Principles of collection . Ą Types of particulate filters . Ą Filter testing and efficiency ratings Gas-phase air filtration . Ą Principles of collection . Ą Types of gas-phase filters Air Contaminant Sizes Various Filter Types Pleated Panel Filters ASHRAE Standards (1) ASHRAE Standards (2) - Typical Performance of a HEPA Filter Exhausting and Purging Basic Principles: . Ą Use ventilation and smoke/purge fans to remove airborne hazards. . Ą Use primarily for internal release or as a final action afteran incident. . Ą Purging should be carefully applied. Issues to Consider . Ą What is the threat? Toxic Industrial Chemicals, particulate, gaseous, chemical, biological? . Ą How clean does the air need to be and what is the associated cost? . Ą What is the current system capacity? . Ą Is there filter bypass and how significant is air infiltrationinto the building envelope? . Ą Will improved indoor air quality offset upgrade costs? . Ą Is system maintenance addressed? Economic Issues to Consider Initial Costs . Ą Filters, housing, blowers . Ą Factors including flow rate, contaminant c once ntrati on Oper ating Cost s Ą Maintenance, replacement filters, utilities, waste disposal Replacement Costs Ą Filter life (factors include continued concentration and particle size distribution, flow rates, etc.) Access to Outdoor Intakes Ultraviolet Germicidal Irradiation All viruses and almost all bacteria (excluding spores) are vulnerable to moderate levels of UVGI exposure UV lamps resemble ordinary fluorescent lamps, but are designed to emit germicidal UV BUILDING DESIGN FOR HOMELAND SECURITY Unit VII-49 Infiltration and Bypass Things Not to Do . Ą Outdoor air intakes should not be permanently sealed. Ą HVAC systems (includes filter upgrades) should not be modified without understanding the effects on building systems or occupants. . Ą Fire protection and life safety systems should only bemodified after careful analysis and review. Summary . Ą CBR threats are real and growing. . Ą Industrial chemicals are readily available. . Ą Military chemicals require specialty expertise. . Ą Most buildings provide a reasonable level of protection. . Ą Inside versus outside building release determines evacuation decision. Unit VII Case Study Activity Chemical, Biological, and Radiological (CBR) Measures Background Purpose of activity: check on learning about the nature of chemical, biological, and radiological agents Requirements Refer to HIC case study and FEMA 426, and answer worksheet questions