Radiological and Laser Safety

Training

Manuals

MANUALS AND PROCEDURES

– ES&H Manual Chapter 9 (Radiological Safety)

http://www-group.slac.stanford.edu/esh/eshmanual/pdfs/ESHch09.pdf

– ES&H Manual Chapter 10 (Laser Safety)

http://www-group.slac.stanford.edu/esh/eshmanual/pdfs/ESHch10.pdf

– Radiological Control Manualhttp://www-group.slac.stanford.edu/esh/documents/RCM.pdf

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Sources of Radiation at SLAC

Various operations and activities at SLAC generate, or

have the potential to generate, ionizing radiation. SLAC’s

sources of ionizing radiation include:

– Accelerator operations generate prompt radiation – Auxiliary devices: guns, klystrons, RF devices– Components or materials in the accelerator housing,

may be made radioactive by accelerator operations– Radioactive sources – X-ray units, Radiation Generating Devices (RGDs)

Note: Some consumer products have naturally-occurring radioactive

elements (thorium welding electrodes, and thorium sand blasting

media)

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Radiation Generating Devices (RGD)

Soil Density Gauges

– Used at construction jobs for soil compact testing

– Has high activity radioactive sources

– RGD Authorization Sheets– Each unit must be approved

and registered BEFORE allowed at SLAC

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Naturally Occurring RAM

Sand Blasting media

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Welding electrodes

Terms and Conditions6

If any subcontractor or lower tier subcontractor are considering purchasing, or bringing such material onto the SLAC site, they shall notify and receive authorization BEFORE bringing these or similar materials to SLAC National Accelerator Laboratory. Review and authorization is needed prior to bringing these items on site. 

Under the Terms and Conditions of the SLAC Blank Order Agreement certain materials are required to have approval of the Radiation Protection Department (RPFO Group Leader or SLAC Radiation Safety Officer) prior to bringing them on site. This includes soil density gauges and naturally occurring radioactive material such as thorium welding electrodes and thorium sand blasting media. Complete list is located on the RP website: http://www-group.slac.stanford.edu/esh/rp/restrictions.htm

Radiation Protection Program

For most people at SLAC, these sources of radiation represent a negligible hazard and the resulting risk remains very low. However, for those who work near these sources, the hazard could be significant without appropriate control and mitigation.

Department of Energy and other Federal, State and local government agencies highly regulate and routinely review all aspects of ionizing radiation.

To protect against radiation hazards, and to comply with the applicable regulations, SLAC has implemented a comprehensive radiation protection program.

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Radiation Protection Program continued

The goal of SLAC radiation protection program is to keep all exposures to its personnel, visitors, public and environment As Low As Reasonably Achievable (ALARA), and far below the applicable regulatory limits.

Engineering and administrative controls are used to control and mitigate the hazards:

– Engineering controls: Shielding, Personnel Protection System (PPS)

– Administrative controls: Beam Authorization Sheets (BAS), Beam Line Authorizations (BLA), Radiation Safety Work Control Form (RSWCF), Radiological Work Permits (RWP), Excavation Permits, and Penetration Permits

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Individual’s Roles and Responsibilities

Everyone at SLAC must follow the radiation safety requirements. This includes training and dosimetry.

TRAINING :1. RWT is required to enter radiological areas or handle/work with

radioactive material2. GERT is required for unescorted access to Controlled Areas or

Radiologically Controlled Areas

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DOSIMETRY: 1. Wear your dosimeter whenever you are in an

area with a sign indicating that a dosimeter is required for entry.

2. Notify RP promptly if your dosimeter is lost or compromised (i.e. exposed to medical, dental, or airport x-rays).

3. Return your dosimeter at the end of the wear period or at the end of the project, whichever is sooner.

4. Contractors who do not return dosimeters will be charged

Contractor Supervisor’s Responsibilities

• Don’t let your personnel conduct a job unless they are trained and authorized to do so.

• Ensure that direct reports are current with their required radiation safety training.

• Ensure radiological systems under your controls are properly maintained.

• Ensure that RP guidance for radiological controls is properly incorporated during the design, maintenance or modification.

• Ensure that an RWP (Radiological Work Permit) is used in every applicable case.

• Do not bring radioactive materials or RGDs to SLAC without prior RP approval.

• Keep radioactive materials in posted areas.• Ensure that visitors, subcontractors, users comply with

SLAC radiation control policies.

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Radiological Posting: Controlled Areas

GERT is the minimum training required for unescorted access to Controlled Areas and

RCA’s• Controlled Areas

– No dosimeters– Form B for escorted individuals– Form C for escorted groups (>5)– Visitors OK (Escort by GERT/RWT)

• RCA’s – No dosimeters if < 8 hours /year– Form B for escorted individuals– Form C for escorted groups (>5)– Visitors OK (Escort by GERT/RWT)

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Radiological Posting: Radiological Areas

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Additional controls required for entry into radiological areas:Radiation Area

High Radiation Area

Contamination Area

RWT IRWP Personnel dosimeter

RWT IRWPPersonnel dosimeterSupplemental dosimeter

RWT IIRWPPersonnel dosimeterPPE

NOTE: No visitors or escorted personnel are allowed in these areas without prior written approval from RP.

Pregnant Worker Advisory

PLEASE BE AWARE Embryo or fetus is more sensitive to

radiation than an adult SLAC fully supports special efforts to

minimize exposure during pregnancy You are encouraged to discuss radiation

monitoring with the Medical Department if you plan, suspect or know that you are pregnant

You must notify your supervisor of your pregnancy if you desire any accommodation

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Laser use in Construction

Manufacturer regulations for alignment lasers (OSHA 21CFR1040.11)

“each surveying, leveling or alignment laser product shall comply with all of the applicable requirements of 1040.10 for a Class 1, 2 or 3R laser product and shall not permit human access to laser radiation in excess of the accessible emission limits of Class 3R.”

Regulations for Laser use in Construction (if Class 2 or higher)

Must satisfy OSHA regulations in 29 CFR 1926.54, including these 3 requirements:

1. Laser operators must have appropriate training and documentation for this training must be provided at the job site.

2. No unattended operation is allowed.3. Area warning signs shall be posted (examples given on

next slide).

*Not meeting above 3 requirements for Class 1 lasers is considered a “de minimus” violation (i.e. without penalty).

Average power levels must not exceed 5mW

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Laser use in ConstructionExamples of Area Warning Signs

Safety for Class 2 and Class 3R visible lasers used in surveying and alignment Class 2 devices are safer to use than Class 3R, because of the lower

power. Both should be used with caution and never stared into. These lasers are not considered a significant hazard for accidental

exposure, because adequate protection is afforded by the eye aversion response to a bright light – response time is about ¼ second. However, a direct exposure from this type of laser can be a startle hazard and cause temporary flash-blindness, after images and glare responses.

Permanent damage is possible if the beam is stared into.

Contact Information

• Contact RP with any questions, concerns or comments on any issues related to personnel or environment radiation protection issues.

• Visit us on the web at:– http://www-group.slac.stanford.edu/esh/rp– Site Access and Identification Badges Policy– Current Radiological Surveys of SLAC Accelerator Hous

ing Locations

– Radiological Classification of Common SLAC Areas– LCW and Discharge Radiological Current Status– Current Radiological Work Permits

• For Radiological Services x4299

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