What Not to Do
Guidance for Protecting the Built Environment

One of the first things to do in preparation for a disaster or emergency is to get to know your building by conducting a walk-through inspection of the building and its systems, including the HVAC, fire protection, and life-safety systems.

During this inspection, compare the most up-to-date design drawings available to the operation of the current systems. This step may require, or benefit from, the assistance of qualified outside professionals.

Without this baseline knowledge, it is difficult to accurately identify what impact a particular security modification may have on building operations.

NIOSH’s “Guidance for Protecting Building Environments” offers a partial list of items to consider during your building walk-through, including the following:

• What is the mechanical condition of the equipment?

• What filtration systems are in place? What are their efficiencies?

• Is all equipment appropriately connected and controlled? Are equipment access doors and panels in place and appropriately sealed?

• Are all dampers (outdoor air, return air, bypass, fire and smoke) functioning? Check to see how well they seal when closed.

• How does the HVAC system respond to manual fire alarm, fire detection, or fire-suppression device activation?

• Are all supply and return ducts completely connected to their grilles and registers?

• Are the variable air volume (VAV) boxes functioning?

• How is the HVAC system controlled? How quickly does it respond?

• How is the building zoned? Where are the air handlers for each zone? Is the system designed for smoke control?

• How does air flow through the building? What are the pressure relationships between zones? Which building entryways are positively or negatively pressurized? Is the building connected to other buildings by tunnels or passageways?

 • Are utility chases and penetrations, elevator shafts, and fire stairs significant airflow pathways?

• Is there obvious air infiltration? Is it localized?

• Does the system provide adequate ventilation given the building’s current occupancy and functions?

• Where are the outdoor air louvers? Are they easily observable? Are they or other mechanical equipment accessible to the public?

• Do adjacent structures or landscaping allow access to the building roof? More than anything else, building owners and managers should ensure that any actions they take do not have a detrimental effect on the building systems (HVAC, fire protection, life safety, etc.) or the building occupants under normal building operation. Some efforts to protect the building from a CBR attack could have adverse effects on the building’s indoor environmental quality. Building owners and managers should understand how the building systems operate and assess the impact of security measures on those systems.

Do not permanently seal outdoor air intakes. Buildings require a steady supply of outdoor air appropriate to their occupancy and function. This supply should be maintained during normal building operations. Closing off the outdoor air supply vents will adversely affect the building occupants and likely result in a decrease in indoor environmental quality and an increase in indoor environmental quality complaints.

Do not modify the HVAC system without understanding the effects on the building system or occupants. This caution directly relates to the recommendation that building owners and managers should understand the operation of their building systems. If there is uncertainty about the effects of a proposed modification, a qualified professional should be consulted.

Do not interfere with fire protection and life safety systems. These systems provide protection in the event of fire or other types of events. They should not be altered without guidance from a professional specifically qualified in fire protection and life safety systems.

Physical Security

Preventing access to a targeted facility requires physical security of entry, storage, roof, and mechanical areas, as well as securing access to the outdoor air intakes of the building HVAC system. The physical security needs of each building should be assessed, as the threat of a CBR attack will vary considerably from building to building. For example, the threat to a large corporate headquarters may be considered greater than the threat to a small retail establishment.

Some physical security measures, such as locking doors to mechanical rooms, are low cost and will not inconvenience the users of the building. These types of measures can be implemented in most buildings. Other physical security measures, such as increased security personnel or package x-ray equipment, are more costly or may inconvenience users substantially. These measures should be implemented when merited after consideration of the threat and consequences of a terrorist attack.

Building owners and managers should be familiar with their buildings and understand what assets require protection and what characteristics about the building or its occupants make it a potential target. By first assessing the vulnerabilities of facilities, building owners and managers can address physical security in an effective manner. While the identification and resolution of building vulnerabilities will be specific to each building, some physical security actions are applicable to many building types. FSM