HAZWOPER Hot, Warm, and Cold Zones

Any employee doing emergency response at their workplace is subject to OSHA’s HAZWOPER standard.

Short for The Hazardous Waste Operations and Emergency Response Standard, HAZWOPER mandates extensive training for employees involved in emergency response. One of those training topics will need to include a discussion about work zones (a.k.a. site control zones or safety zones).

So what does a response scene typically look like? Well, it will consist of three zones: the exclusion zone, the contamination reduction zone, and the support zone.

The Exclusion Zone

The Exclusion Zone (often referred to as the “Hot Zone” or “Red Zone”) is the area that has actual or potential contamination that surrounds the emergency response incident. Most importantly, this is where the actual response takes place.

Activities within the Exclusion Zone include, but are not limited to:

• Site characterization and assessment,
• Hazard detection and monitoring,
• Controlling and confining releases, and
• Actual cleanup work.

As you can probably guess, not just anybody should be entering the Hot Zone. Only those employees trained to HAZWOPER standards may enter.

The Contamination Reduction Zone

The Contamination Reduction Zone (often referred to as the “Warm Zone” or “Yellow Zone”) is the transition area between the Exclusion and Support Zones. This area will directly support the activities taking place in the Hot Zone.

Activities within the Contamination Reduction Zone include, but are not limited to:

• Decontamination of equipment and personnel,
• Initial first aid for injured employees,
• Equipment resupply (such as refilling air tanks), and
• Temporary rest area for responders.

Even though the Warm Zone is a little safer than the Hot Zone, only trained HAZWOPER employees should enter the Warm Zone since there is still potential exposure to hazardous substances.

The Support Zone

The Support Zone (often referred to as the “Cold Zone” or “Green Zone”) is the area of the site that is free from contamination.  This area will be used as a planning and staging area.
Activities within the Support Zone include, but are not limited to:

• Command post operations,
• Logistical support,
• Staging,
• Medical support, and
• Worker rest areas (such as eating and drinking areas).

Even though Cold Zone is safe and free of contaminants, if you are engaging in emergency response related activities (such as providing support to the actual responders), you will need HAZWOPER safety training.

Figure 9-1 shown below is taken from OSHA's "Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities."    

Tags: compliance, emergency, HAZWOPER, osha, response