LP-1: Low-Level Passive Protection
• Select systems to minimize normal exposure.
◦ Dilute indoor air and reduce recirculation.
◦ Minimize leakage in HVAC system and in building (external and internal).
◦ Add filtering as needed for healthy workplace.
◦ Protect air intakes to reduce air contaminants.
◦ Use construction methods and materials that reduce chemical exposure.
• Consider security, site selection, and operational activities that have dual-use advantages for building protection.
LP-2: High-Level Passive Protection (LP-1 + options specific to protection from biological and chemical threat agents)
• Use upgraded protection from biological and chemical threat agents compared to LP-1.
◦ Upgrade filters (particulate and adsorption) specific for biological and chemical threat agents.
◦ Use zoning with graded pressurization (compartmentalized).
◦ Provide local air-washing vestibules.
◦ Protect air intakes specifically to reduce biological and chemical threats.