Zone 2: Warm Zone

Between the Hot zone and the support or cold zone is the contamination reduction zone or warm zone which provides a transition between contaminated and clean zones. This zone serves as a buffer to further reduce the probability of the clean zone becoming contaminated or being affected by other existing hazards. It provides additional assurance that the physical transfer of contaminating substances on people, equipment, or in the air is limited through a combination of decontamination, distance between Hot and Cold zones, air dilution, zone restrictions, and work functions.

Decontamination procedures take place in designated areas within the Warm zone. They begin at the hotline. Normally there are two:

• One for personnel
• One for heavy equipment

Depending on the size of the operation, more than two may be necessary. Exit from the Hot zone must be through a contamination reduction corridor to the warm zone. As operations proceed, the area around the decontamination station may become contaminated but to a much lesser degree than the Hot zone. On a relative basis, the amount of contaminants should decrease from the hotline to the cold zone due to the distance involved and the decontamination procedures used.

The boundary between the cold zone and the warm zone is the contamination control line. It separates the possibly low contamination area from the clean support (cold) zone. Access to the warm zone from the cold zone should be through a control point. Personnel entering this area should wear the prescribed personal protective equipment, if required, for working in the warm zone. Entering the cold zone requires removal of any protection equipment worn in the warm zone. The personnel stationed in the warm zone are usually the site safety officer, Personnel Decontamination Station (PDS) operators, and the emergency response personnel. The Warm Zone must be well designed to facilitate decontamination of equipment personnel, and samples.

Emergency response – transport for injured personnel (safety harness, stretcher), first-aid equipment such as bandages, blankets, eye wash, splints, and water, and containment equipment (absorbent, fire extinguisher).

Equipment resupply – air tank changes, personal protective clothing and equipment such as booties and gloves, sampling equipment (bottles and glass rods), and tools.

Sample packaging and preparations for on site or off site laboratories.