Controlled Zones and Limits

Upon completion of this lesson, the participants will demonstrate their knowledge and understanding of the information by obtaining a score greater than or equal to 80% on a written examination. The information presented in this lesson plan may be part of an overall exam or be the only information for which the student is examined. Terminal Objective

Standards and conditions apply to all enabling objectives. They include under the examination ground rules, without the use of training materials or outside assistance, and utilizing information presented in this lesson plan. Upon completion of this lesson each participant will be able to: Enabling Objectives

Define “clean area”. Define “ restricted area” and the identification mechanisms utilized. Define Radiological Control Area and the identification mechanisms utilized, and state the requirements for entry.

Enabling Objectives Describe the Radioactive Material posting, labeling, marking and use requirements. Define Radiation Area, posting requirements and precautions, and determine the posting based upon a dose rate.

Enabling Objectives Define High Radiation Area, posting requirements and precautions, and determine the posting based upon a dose rate. Define Locked Radiation Area, posting requirements and precautions, and determine the posting based upon a dose rate. Define Very High Radiation Area, posting requirements and precautions, and determine the posting based upon a dose rate.

Enabling Objectives Define “Hot Spot”. Define Contamination Area, posting requirements and precautions. Describe Fixed contamination in termsof radioactive material label requirements and markings. Define Airborne Radioactivity Area and posting requirements. List contamination limits for clean area release, personnel, protective clothing.

Restricted Area

RADIOLOGICALLY CONTROLLED AREA MONITORING DEVICE REQUIRED NOTIFY RADCON PRIOR TO ENTRY NO EATING, DRINKING, OR SMOKING Radiological Control Area  Radiological hazards exist or the potential for radiological hazards exist  Buffer zone between areas with radiological hazards and the “clean area”  Designated by yellow and magenta rope, ribbon, or chain as a boundary and a radiological posting

RADIOLOGICALLY CONTROLLED AREA MONITORING DEVICE REQUIRED NOTIFY RADCON PRIOR TO ENTRY NO EATING, DRINKING, OR SMOKING Radiological Control Area Entry Requirements  Personnel must have Radiation Worker training prior to entry.  Entry to and exit from the area shall be via designated access points.  Personnel shall monitor themselves for contamination prior to exit.

RADIOACTIVE MATERIAL Radioactive Material  Posting required when radioactive material is stored or used in excess of 10 times the quantity listed in appendix C of 10CFR20.  Radioactive material labeled per 10CFR & 10CFR Labels require Radiation levels Contamination levels Kinds of material Identity of person who labeled the material Tools & equipment not labeled will be marked

RADIOACTIVE MATERIAL Radioactive Material  Movement/storage a in manner to prevent the spread of contamination and/or excessive exposure & prevent the loss of control in transient.  Removal from RCA requires Radcon approval. Labels require Radiation levels Contamination levels Kinds of material Identity of person who labeled the material Tools & equipment not labeled will be marked

Radiation Area Dose rates 5 30 cm Work is planned and controlled to eliminate excessive exposure.

High Radiation Area Dose Rates >100 mrem/hr  Barricaded and conspicuously posted  Entry controlled through the use of Radiation Work Permits (RWP) Any individual permitted to enter shall be provided with: A radiation monitoring device which continuously indicates the radiation dose rate in the area A radiation monitoring device which continuously integrates the radiation dose rate in the area and alarms when preset integrated dose is received Continuous Radcon coverage

Continuous Radcon Coverage is required for entry. Strict key control for lock and entry. Locked High Radiation Area Dose rates in the area exceed 1000 mrem/hr. Must follow the requirements set forth in 10CFR20 Thus the entryways are locked or guarded

Very High Radiation Area Dose rates exceed meter In addition to the requirements for a High Radiation Area, the licensee shall institute additional measures to ensure that an individual is not able to gain unauthorized or inadvertent access. Entry requires approval of the Radcon Superintendent and may require further approval.

Hot Spot Hot Spots are normally caused by “crud” buildup inside the piping. Information posting to inform worker of an area exist with a significant radiation level in correspondence to the surrounding area. Contact dose rate greater than or equal to 100 mrem/hr Contact dose rate 5 X’s higher 30 cm dose rate.

On August 17, Performing the monthly survey Dose rate > cm- outside HRA posted boundary Dose rates - ankle level - RO-2 ion chamber meter - Source of radiation - ankle level Event cause -inconsistent techniques employed by technicians -some ankle height to eight-foot elevation - others waist height to the eight-foot -procedures not clear guidance all levels of a boundary Operating Experience

No personnel overexposure occurred - potential for exposure existed Corrective actions – extend HRA, Validating new boundary, updating radiological area status sheet, briefing technicians to perform surveys to address whole body, verifying other HRA boundaries, rocedures revised to clearly define dose rate measurement techniques Event not significant -no overexposure from unposted area Event noteworthy - inconsistent survey techniques result unposted HRA Operating Experience

Contamination Area Contamination Areas  Conspicuous boundaries - rad-ribbon, rad-rope, rad-tape, and step-off pads  Limitations - radiation tape and/or radiation hazard tags.  Space limitation - floor drains, electrical panels, sample sinks, etc. Loose contamination in excess of 1000 dpm/100cm2 beta/gamma 20 dpm/100cm2 alpha  Levels – minimum- decontamination  Protective clothing - required  Open cuts, wounds, skin rashes, and infections - protected

Fixed Contamination Items with fixed contamination will have to be tagged as Radioactive Material when levels are in accordance with 10CFR and 10CFR Levels are less than Rad material but >100 cpm beta/gamma and/or >30 cpm alpha Item is marked to designate RCA use Fixed contamination - contamination is not transferred or detected by smear survey. Transferable through operations such as grinding, welding, etc.

An airborne radioactivity area is an area, room, or enclosure in which airborne radioactive material composed wholly or partly of licensed material exist in concentrations exceeding 30 percent of the limits in site procedures or 10 CFR 20 Appendix B, Table 1, when isotopic analysis is available. If the isotopes are unidentified, the limits are: Alpha – 6 x Beta/gamma – T ½ >2 hr – 3 x T ½ <2 hr – 1 x Airborne Radioactivity Area

Total Radioactivity (Direct Survey)Removable c Alph a b Beta- Gamma a Alpha b Beta- gamma AREA/ITEM(cpm) (dpm/100 cm 2 ) Clean zone surfaces or material release Personal clothing30100N/A e or skin surfaces.

Total Radioactivity (Direct Survey)Removable c Alpha b Beta- Gamma a Alpha b Beta- gamma AREA/ITEM(cpm) (dpm/100 cm 2 ) Respirators or cartridges. C-zone clothing d 1000 d and respiratory equipment excluding face mask and cartridge

June 24, 2002, Davis Besse -containment decon tent - mirror insulation – high contamination levels Decon mirror insulation - workers questioned - boric acid on mirror insulation Rad tag smearable - 30,000dpm/100cm 2 Contacted technician – 5,000,000dpm/100cm2 1.5 rad/hr. Decon tent - up to 1,000,000 dpm/100cm 2 Decon tent prior -20,000 to 50,000 dpm/100cm 2 Air sampler % DAC OE 13939

One worker - minor contamination on modesty garments, No intakes Caused by mislabeling of the bag -wrong tag on bag after initial tagging Contamination control - upgraded - survey all insulation prior to decon Event -not significant -no excessive exposure or potential Event is NOTEWORTHY - work practices resulted in significantly higher than expected smearable contamination levels OE 13939