Site Control Measures
Site Control is established by isolating and controlling entry/exit.
The purpose of site access control is to control the movement of people
into and out of the area of concern and to limit the potential
for increased spread and exposure to the agent and also monitoring the
agent for indications of spread. Site Access Control is established by
setting up Control Lines (barrier type) and establishing Control Zones.
To ensure against the accidental spread of hazardous agents by workers
from contaminated areas to clean areas, zones will be delineated where
intrusive investigative activities occur, and the flow of personnel in
these zones will be controlled.
The establishment of work zones will help ensure:
- personnel are properly protected against the hazards present
where they are working,
- work activities and contamination are confined to the appropriate
- personnel can be located and evacuated in an emergency
This site is divided into three (3) major zones, described below and
shown in Figure 7-1. These zones are characterized by presence
or absence of biological and chemical hazards and the activities performed
Zone boundaries are clearly marked at all times and the flow of personnel
among the zones is controlled.
The site is monitored for changing conditions that may warrant adjustment
of zone boundaries. Zone boundaries are adjusted as necessary to
protect personnel and clean areas. Whenever boundaries are adjusted,
zone markings are also changed and workers are immediately notified of
Work zones used during deployment activities, as deemed necessary by
the Incident Commander with Incident Safety Officer assistance, will
- Exclusion (HOT) Zone—the potentially contaminated or
unsafe areas. Personnel and equipment will enter and exit the Exclusion
Zone from the designated access points in the Contamination Reduction
Zone (CRZ), shown in Figure 7-1. Personnel in the Exclusion Zone will
adhere to the established work procedure
- Contamination Reduction (WARM) Zone [CRZ]—the area where decontamination
of PPE takes place. Based on monitoring results, the CRZ boundaries
may be adjusted to ensure that the Support Zone remains uncontaminated.
Workers and equipment exit the Exclusion Zone through the designated
access point(s) into the CRZ. Workers and equipment are then
decontaminated in the CRZ, according to the procedures specified in
the Decontamination section of the HASP. Workers and equipment
then exit the CRZ into the Support Zone through the designated access
points, shown in Figure 7-1. If necessary, emergency decontamination
procedures are implemented. Emergency decontamination procedures are
described in the emergency response program.
- Decon (Decontamination)
Corridor--The Decon Corridor is the area between the Hot Zone Control
Line and the Warm Zone Control Line where decontamination of personnel
and equipment takes place. Entry Teams enter and exit the Hot Zone
through the access control points that are located at each end of the
- Support (COLD) Zone—the uncontaminated area where
workers should not be exposed to hazardous conditions. The Support
Zone is the clean area of the site, beyond the outer boundary of the
should be no contamination in this zone. Administrative, clerical,
and other support functions are based in the Support Zone. Air and
surface monitoring are conducted in the Support Zone as needed to ensure
that it remains uncontaminated. If contamination is detected,
zone boundaries are adjusted until corrective action is taken and monitoring
results indicate that this zone is again uncontaminated.
A "hotline" where personnel routinely enter or exit the exclusion
zone will be located upwind from the exclusion zone, whenever possible.
All work zones will be adequately marked using signs and fencing, traffic
cones and caution tape.
Access to the exclusion zone and CRZ will be strictly limited to individuals
who meet all medical monitoring, training, and PPE requirements.
Visitors must receive appropriate training, be medically qualified, wear
the appropriate level of protection, receive a safety briefing, and will
be escorted by qualified personnel. Visitors who do not meet the specified
requirements will remain in the support zone.
Criteria for Establishing Zones
The initial control zone to be established will be the Warm Zone by placing
yellow “Warm” Zone Control Line barrier tape around the incident.
People will be evacuated from any area within this zone.
No person shall exit or be removed from a Hot Zone until they have been
properly decontaminated or it has been confirmed to be safe to remove them
without first being decontaminated.
No person shall be allowed into a Warm or Hot Zone without the proper level
of personnel protective equipment as specified by the Safety Officer.
No person shall enter a Hot Zone prior to the establishment of a Decontamination
Once entry has been made into the Hot Zone, no one who remains in the Warm
Zone will be allowed to exit into the Cold Zone until they have been decontaminated
or checked for contamination.