ETL 1110-3-490
13 May 98
APPENDIX B
COLLECTIVE PROTECTION REQUIREMENTS
FOR EXISTING AND NEW FACILITIES
B-1. Facility Classification for Collective Protection Design.
New collective protection facilities with an integral contamination control area (CCA) will be
designed in accordance with TM 5-855-1 and other criteria as designated by the using command or
authority having jurisdiction. Existing and new facilities can be separated into four classes that
reflect their potential to support the integration of a collective protection (CP) system.
a. Class I. A Class I facility is capable of fully integrating the CP overpressure system with the
facility heating, ventilating, and air-conditioning (HVAC) system. The HVAC system may not be
specifically designed for a CP overpressure system, but it is capable of fully maintaining the facility
temperature during CP system operation. The CCA can be permanent construction inside the
facility or under an open-air overhang, roofed shelter, or tent.
b. Class II. A Class II facility HVAC system is capable of partial integration of the CP
overpressure system. The HVAC system may require upgrades to existing ductwork and isolation
of the ductwork used for normal HVAC facility operations. The HVAC system may not be
capable of maintaining original design conditions without modification and may require supplemen-
tal heating and cooling to be provided with the CP system. The CCA can be permanent construc-
tion inside the facility or under an open-air overhang, roofed shelter, or tent.
c. Class III. A Class III facility HVAC system is not capable of integrating the CP over-
pressure system. The facility design temperatures cannot be maintained without supplemental
heating and cooling from the CP overpressure system. The CCA is under an open-air overhang,
roofed shelter, or tent.
d. Class IV. A Class IV facility is not capable of maintaining overpressure without extensive
sealing. Therefore, it is only suitable for use with the addition of an inflatable CP shelter. This
type of arrangement allows the existing HVAC system to partially or fully maintain the facility
design temperature outside the inflatable shelter.
B-2. Guidance.
a. Designation for Collective Protection. The commander or authority having jurisdiction
determines if facilities are susceptible to a chemical threat and which facilities require collective
protection.
B-1