The Exclusion Zone

DOE-EM-STD-5503-94

Reduce the accidental spread of hazardous substances by workers or equipment from the

contaminated areas to the clean areas;

Confine work activities to the appropriate areas, thereby minimizing the likelihood of

accidental exposures;

Facilitate the location and evacuation of personnel in case of an emergency; and

Prevent unauthorized personnel from entering controlled areas.

When establishing the work zones at a site, the site map can provide a useful format for compiling

the relevant data. In the absence of sampling results, site maps can provide essential information

on potential and suspected hazards and potential exposure pathways.

Although a site may be divided into as many zones as necessary to ensure minimal employee

exposure to hazardous substances, the three most frequently identified zones are the Exclusion

Zone (or "hot zone"), the Contamination Reduction Zone, and the Support Zone (or "clean

zone"). Movement of personnel and equipment between these zones should be minimized and

restricted to specific access control points to prevent cross-contamination.

9.3.1. The Exclusion Zone

The Exclusion Zone is the area where contamination is either known or expected to occur and

where the greatest potential for exposure exists. The outer boundary of the Exclusion Zone,

called the Hotline, separates the area of contamination from the Contamination Reduction Zone.

The Hotline should initially be established by visually surveying the site and determining the

extent of hazardous substances, discoloration, or any drainage, leachate, or spilled material

present. Other factors to consider in establishing the Hotline include:

Providing sufficient space to protect personnel outside the Exclusion Zone from potential

fire or explosion,

Allowing an adequate area within which to conduct site operations, and

Reducing the potential for contaminant migration.

The Hotline should be physically secured (e.g., using chains, fences, or ropes) or clearly marked

(e.g., using lines, placards, hazard tape, and/or signs). During subsequent site operations, the

boundary may be modified and adjusted as more information becomes available. In addition, the

Exclusion Zone may also be subdivided into different areas of contamination based on the known

or expected type and degree of hazards or the incompatibility of waste streams. If the Exclusion

Zone is subdivided in this manner, additional demarcations (e.g., "Hazards Present" or

"Protection Required") may be necessary. For sites where radiological contamination exists,

procedures for establishing and posting of radiological zones should be developed and included

in this chapter. Procedures should be in accordance with the DOE Radiological Control Manual.

Access to and from the Exclusion Zone should be restricted to Access Control Points at the

Hotline. Access Control Points are used to regulate the flow of personnel and equipment into

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