Support zone

The support zone also is ealled the elean zone. This is where administrative and support funetions neeessary to maintain site eontrols are loeated. The support zone loeation should be based on the following six general eriteria  

Normal work elothes are appropriate for the support zone. PPE worn for the hazardous waste work should remain in the CRZ/C. At some point, this PPE will be deeontaminated or paekaged for transport and disposal or deeontamination. Separate support zone faeilities may not be needed where site faeilities are readily available and near to the worksite, and if elose eommunieation is maintained. Eor multiple hazardous waste operations eondueted in elose proximity, it is possible to design one support zone to serve several operations. This will depend on the logisties of the projeet. 

A properly equipped support zone may eonsist of a single trailer or may be eomposed of multiple faeilities sueh as a eommand post, medieal station, equipment and supply eenters, field laboratory, and administrative areas. 

The following elements should be taken into eonsideration when determining the loeation and setup of the support zone  

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If the area and eorridor ean be maintained free of safety hazards arising from the hazardous waste operation, the work probably would not fall under the requirements. In this ease, the area and eorridor would eonstitute a temporary support zone. Beeause the work involves eleetri-eal utilities, it would fall under the most proteetive standard of praetiee, sueh as OSHA s Eleetrieal Standard or the National Eleetrie Code (NEC). Also, there may be other requirements that apply. Administrative eontrols sueh as HAZWOPER-trained eseorts are used to make eertain that the utility workers are not exposed to any hazards from the operation. The proeedures to be followed are doeumented in the site-speeifie HASP [1]. 

Establishing exehision, eontamination reduetion, and support zones... 

Work zones are often temporary. Many times, onee the work has been eondueted, the zone boundaries ehange and sometimes beeome support zones. Temporary work zones ean be used to eflfeetively manage regulatory seope. Area and personnel exposure monitoring is erueial in order to verify that zoning, eontainments, work praetiees, and proeedures have been designed appropriately and maintain worker health and safety. 

The CRZ/C s primary purpose is to keep the support zone free of eontaminants and hazards. The size and loeation of the CRZ/C should be based on the stability of site eonditions, the potential for dispersion of eontaminants and for unexpeeted events, and the proximity of unin-... 

The names, number, and types of zones vary based on the aetivities at the worksite. The important thing to remember is that work zones are established to proteet the workers and the publie. Everyone on the site should understand the hazard(s) and eontrol(s) neeessary to support eaeh identified zone. Wind direetion was mentioned as an important eri-terion in ehoosing the support or elean zone. In most parts of the eountry, wind direetion ean be highly variable. If this is the ease at a given site, how should the support zone be handled The answer may vary based on the eonditions. 

To illustrate this point, let s eonsider the example of a superfund ehemieal waste landfill remediation job. In this example, we will need to determine the eontaminants of eoneern. After making this determination, we next need to assess the eontaminants and how they may migrate from the site. We need to determine if ehanges in the wind direetion oeeur, how frequently, and how workers in the support zone will be aflfeeted. In most eases, the likelihood for workers in the support zone to be affeeted is minimal. 

If dust is being ereated, alternatives should be eonsidered. One alternative may be a ehange of loeation of the support zone. This may be more diflfieult than it sounds. Many times the support zones are trailers,... 

For most hazardous waste sites with proper planning the situation is known before remediation activities begin. The support zone location needs to be carefully considered at the planning stages of the project. A better solution to the theoretical problem at hand would be to move the support zone further from the source of contamination. If the support zone can be placed far enough away, the likelihood for exposure at the support zone is minimized. 

However, moving the support zone farther from the source of contamination often brings up logistical problems associated with the distance. The logistics should be considered at all times. No matter how open the space is, there are always distance constraints. 

In some cases, decontamination workers wear the same level of PPE as workers entering the controlled area or exclusion zone. In others, decontamination workers are sufficiently protected by wearing a lower level of PPE. In many instances, level D protection is not acceptable in the CRZ. In addition, all decontamination workers should be decontaminated before entering the support zone. Appropriate equipment and clothing for protecting decontamination workers should be planned by the project team [2]. 

Many hazardous waste activity worksites are temporary and are established at remote locations with limited sanitation facilities. Decontamination is conducted either in the contamination reduction zone or the radiological buffer zone, whereas sanitation functions are performed either in the support zone or outside the boundaries of the hazardous waste activities worksite after decontamination has been completed. 

Forty-hour training was required for personnel entering the exclusion zone, and additional supervisory training was required for site supervisors. Site control procedures described in the Site C contractor s SSAHP included maintenance of site control logs at each access point, use of red tape or chainlink fencing to demarcate hot zones, and use of the buddy system in all exclusion and contamination reduction zone areas. Site communications relied almost exclusively on visual sighting of employees the plan did not describe the use of two-way radios. This suggested that all employees in hot zones can be observed continuously from the support zones. 

Signiflcant deficiencies in site control procedures existed at Site K. For example, the Site K subcontractor had not established a contamination reduction zone (CRZ), to physically separate the support zone from the exclusion zone, as required in the site plan. 

Site D lacked a sufficient CRZ and also lacked access/egress control for the exclusion zone. The site control plan did not accurately identify the function of the CRZ as a buffer zone between the exclusion zone and the support zone, and there was no buffer area between the decontamination pad and the road that runs adjacent to the pad, marked as a support zone. Also, an exclusion zone log-in procedure for tracking personnel who enter and exit this zone was not used on site as called for in the SSAHP. 

Subcontractor may be used in support zone or nonhazardous site activities. Eor limited activities at a hazardous waste site, the scope of work must be reviewed with the health and safety professional before work is started (examples landscape service, electricians, software development, training, etc.). The subcontractor must meet the following minimum requirements ... 

Are work zones ineluding Exelusion Zone (EZ), Contamination Reduetion Zone (CRZ), and Support Zones adequately demareated and is restrieted aeeess enforeed [OSHA Referenee. 120(d)(3)]... 

Support zone. This is the uncontaminated area where workers should not be exposed to hazardous conditions (Table 16.12). 

Modify its location, if necessary, as more information becomes available The support zone activities are briefly presented in Table 16.12. 

At a hazardous waste site, remediation and decontamination facilities should be located in the CRZ, that is, the area between the exclusion zone (the contaminated area) and the support zone (the clean area). The level and types of remediation and decontamination procedures required depend on several site-specific factors ... 

Rescued persons who have been exposed only to arsine gas do NOT need decontamination, and rescue personnel in the Support Zone or other clean areas do not need any specialized protection if everybody has already been decontaminated or all victims now in the support areas have been exposed only to arsine gas. ... 

Contamination Control Line The established line around a contamination reduction zone that separates it from the support zone. 

Soap, brushes, sponges, and other equipment used for decontamination shouid be piaced in atrashcan and not carried into the Support Zone (on-scene) or the Coid (Ciean) Zone (hospitai setting). 

In establishing a hazardous materials emergency response, three hazard zones should be established, namely, the exclusion, contamination reduction, and support zones. In the exclusion zone, a high level of contamination is present and overexposure, without the use of PPE, is likely. Therefore, PPE is typically required. Personnel, with the exception of skilled support personnel, must be trained. The exclusion zone may be activity-specific for operations that can generate high levels of contaminants. 

The support zone is where the majority of the incident command structure is located. No exposures are likely in the support zone. No training or PPE is required in the support zone. 

In systems with return flows, as is the case in floating or supported zones, stationary roll cells were shown not to exist in slots heated from the side. Surface waves were found to be the prevailing cause of instability at very low Pr. However, it seems tenuous to try to extrapolate their results to the return flows with significant inertial effects and surface heating which we studied because the nonlinear inertia terms have a profound influence on the velocity profile, the surface deflection and the pressure distribution therefore they would influence strongly all modes of instability. 

The Support Zone (also known as the cold or green zone) is where the Incident Commander, support teams, press, medical treatment areas, and ambulances are located. It is usually upwind, uphill, and a safe distance from the incident. 

V. Victim management Victim management includes rapid stabilization and removal from the Exclusion Zone, initial decontamination, delivery to emergency medical services personnel at the Support Zone perimeter, and medical assessment and treatment in the support area. Usually only the HazMat team or other fire department personnel with appropriate training and protective gear will be responsible for rescue from the hot zone, where skin and respiratory protection may be critical. Emergency medical personnel without specific training and appropriate equipment must not enter the hot zone unless it is determined to be safe by the Incident Commander and the medical officer. 

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