Bioaccumulative

Substances that concentrate in living organisms as they breathe contaminated air, drink or live in contaminated water or eat contaminated food rather than being eliminated through natural processes.

Brownfield

Real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.

Capability

The ability and capacity to attack a target and cause adverse effects.

Cascading event

The occurrence of one event that causes another event.

Casualties

Deaths or injuries resulting from an event.

Catastrophic incident

Any natural or manmade incident, including terrorism, which results in extraordinary levels of mass casualties, damage, or disruption severely affecting the population, infrastructure, environment, economy, national morale, and/or government functions. A catastrophic event could result in sustained national im-

pacts over a prolonged period of time; almost immediately exceed private sector authorities in the impacted area; and significantly interrupt government operations and emergency services to such an extent that national security could be threatened.

Emergency preparedness practices

Practices that develop the resources needed to support emergency response.

Hazard

An inherent physical or chemical characteristic that has the potential for causing harm to people, the environment, or property.

Hazard exposure

The geographical areas that could be affected by a hazardous incident.

Hazard mitigation practices

Practices that provide passive protection to persons and property at the time an incident occurs.

Hazardous incident

An event that is perceived by some segments of society as producing unacceptable impacts or as indicating the danger that such impacts might occur in the future.

Inherently safer processes

A process can be described as “inherently safer” than other process alternatives in the context of one or more specific hazards if those hazards are eliminated or greatly reduced relative to the alternative processes, and if the process characteristics which eliminate or reduce the hazards are a permanent and inseparable element of the process. This means that safety is “built in” to the process, not added on. Hazards are eliminated, not controlled, and the means by which the hazards are eliminated are so fundamental to the design of the process that they cannot be changed or defeated without changing the process.

Intent

The desire or motivation of an adversary to attack a target and cause adverse effects.

Lethal Dose 50 (LD₅₀)

The dose at which 50 percent of an exposed animal model population dies.

Links

The means (road, rail, barge, or pipeline) by which a chemical is transported from one node to another.

Multiple terrorist incident

Terrorist attacks occurring simultaneously or in a series at a single location or multiple locations.

Nodes

A facility at which a chemical is produced, stored, or consumed.

Pathways

The sequence of nodes and links by which a chemical is produced, transported, and transformed from its initial source to its ultimate consumer.

Physical vulnerability

The susceptibility of persons and structures to the impacts of a hazardous incident.

Red teaming

As used here, a group exercise to imagine all possible terrorist attack scenarios against the chemical infrastructure and their consequences.

Risk

The result of a threat with adverse effects on a vulnerable system.

Single terrorist incident

A terrorist attack at a single location.

Social amplification

The many ways in which information about risks is amplified by some social processes and reduced by others.

Threat

The intent and capability to adversely affect (cause harm or damage to) the system by adversely changing its states.

Tipping

Concept (from the tipping of a scale) that refers to many others in the supply chain simultaneously investing in security measures because one or more units in the supply chain have done so.

Vulnerability

The manifestation of the inherent states of the system (e.g., physical, technical, organizational, social, cultural) that can be exploited by an adversary to adversely affect (cause harm or damage to) that system.

Vulnerable zones

Areas around a facility in which people could, but would not necessarily, be exposed to harm by a worst-case event.