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Radiation Awareness Module

Health, Safety & Environment Department

April 18, 2005

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Outline

• Introduction

• Background

• Radiation Exposure

• Risks

• Monitoring

• Controls

• Emergency

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Introduction

CLS HS&E Policy

“CLSI is committed to provide a safe and healthful working environment for all staff and to protect the general public and the environment from unacceptable risks”

»Approved by CLSI Executive Director »Passed by CLSI Board of Directors

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Introduction

• Health Safety Orientation (HSO) and the Radiation Awareness Module (RAM) must be completed before unescorted access to the experimental areas is permitted.

• Untrained individuals must be escorted by personnel with the required training. The escort is responsible to ensure the individual(s) comply with all safety requirements.

• RAM expires after 2 years - retraining is required.

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Introduction

• The CLS facility is licensed to operate by the Canadian Nuclear Safety Commission (CNSC). The license is posted on the HSE bulletin board.

• Radiation producing devices such as electron beam accelerators and radioactive materials are used at the CLS.

• This training is to ensure individuals are aware of the potential radiation hazards, risks and controls that are associated with these activities.

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BackgroundWhat is Radiation?• Radiation is energy transferred through space and matter.• Ionizing radiation consists of particles (alpha, beta, neutron) or

waves (xray, gamma) of energy emitted from radioactive atoms or radiation producing machines.

• Ionizing radiation has enough energy to remove electrons from atoms.

• Non-ionizing radiation (radio waves, visible light, microwaves) does not have enough energy to remove electrons from atoms.

• When ionizing radiation travels through a medium it deposits (loses) some of its energy to the medium. If the energy is deposited in a person, he or she receives a radiation dose.

• Radiation dose is reported in milli-Sieverts (mSv)

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Background

Natural Sources of Radiation• Humans are constantly exposed to ionizing

radiation from natural sources.– Eg… cosmic rays, radioactive elements in the

earth, ingestion of radionuclides in food, inhalation of radon gas.

• The average annual radiation dose to the general population in Canada from natural sources is about 2 mSv per person.

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Background

Human-made Sources• Human-made sources contribute an additional

radiation dose. • These sources include:

– Medical• x-rays, nuclear medicine

– Consumer products • TV sets, Smoke Detectors

– Fallout from nuclear weapons testing– Nuclear reactors for power generation

• Average annual radiation dose to the general population in Canada from human-made sources is about 0.6 mSv per person

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Background

Natural Sources

Human-made

Sources

CLS Worker Maximum Exposure

2003

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

mSv/yr

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Radiation Exposure

• There is a slightly increased risk of developing cancer from chronic exposure to low levels of radiation. The amount of risk depends on the amount, duration, and the distribution of the radiation exposure.

• The increased risk of cancer from occupational exposure is small compared to the normal cancer rate.

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Radiation Exposure

Occupational Exposure Limits• Canadian Nuclear Safety Commission (CNSC) sets the

radiation dose limits for occupationally exposed workers in Canada.

• Dose Limits:– Nuclear Energy Worker (NEW):

• ONE-YEAR = 50 mSv• FIVE-YEAR = 100 mSv• ONE-YEAR AVERAGE = 20 mSv• Pregnant NEW: 4 mSv for the balance of pregnancy

– General Public (Non NEW): 1 mSv per year

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Risks

Statistics• In a population of 10,000 people, 3,000 will contract

cancer in their lifetime. • Of the 3,000 that develop cancer, approximately 2,000 will

die from their cancer. • If all 10,000 people were to receive 10 mSv (in addition to

the radiation dose from natural background and man-made sources), an additional 4 deaths may occur due to radiation induced cancers.

• This small effect cannot be "seen" in the normal variation of the death rates, and therefore must be calculated.

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Risks

Industry Type or Activity Estimated Days of Life Expectancy Lost

Smoking 20 cigarettes a day 2370 (6.5 years)

Overweight by 20% 985 (2.7 years)

Mining and Quarrying 328

Construction 302

Agriculture 277

Government 55

Manufacturing 43

Radiation – 3.4 mSv/yr for 30 years

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Radiation - 1 mSv/yr for 70 years 34

Occupational Comparisons

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Risks

Prenatal Exposure• An embryo/fetus is especially sensitive to ionizing

radiation due to the rapid division rate of the developing cells.

• Any female Worker must inform in writing her immediate supervisor and HSE Manager as soon as she is aware of her pregnancy.

• Contact the CLSI HSE Dept. for more information.

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Monitoring

• To ensure that exposures are maintained As Low As Reasonably Achievable (ALARA), individuals are monitored for radiation exposure.

• CLS has both personnel and area radiation monitoring programs.

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Monitoring

Personal Monitoring• TLD

– small inorganic crystals that absorb energy when exposed to radiation

• TLDs used at CLS respond to beta, gamma, x-rays and neutrons

• They are processed quarterly, but personnelare only notified of results if they receive a radiation dose• Most results at CLS are below the detection limits of the TLD

Beta Window

TLD

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Monitoring

Personal Monitoring• Electronic Personal Dosimeter (EPD)

– Detects Gamma radiation– Real time dose rates– Alarm– Digital readout– For temporary use at discretion of HSE– Available in the Control Room– EPDs must be returned to the Control Room at the end of

each day– Should not be dropped or banged

EPD

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Monitoring

Personal Monitoring• TLDs and personal monitoring devices shall be worn on the

front of the torso. • TLDs must be stored in the designated location when not in

use • TLD racks are located near the main and west entrances

TLD Rack

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Monitoring

Active Area Monitoring• Fixed location radiation monitors• Local audible alarm if preset radiation levels

exceeded• Radiation levels also displayed in Control Room

Area Radiation Monitor

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Monitoring

Passive Area Monitoring• Radiation measurements from TLDs strategically

located throughout the facility.• Longer term monitoring at specific locations• Help reconstruct an individual dose in the absence

of personnel dosimeter data

Passive Area Monitors

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Monitoring

Radiation Surveys

• Radiation surveys using portable survey instruments are carried out periodically throughout the CLS Facility

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Controls

• Engineering and administrative controls are in place to protect personnel from exposure to radiation and radioactive material.

• Engineering controls include access restrictions (ACIS), shielding, and radiation monitors.

• Administrative controls such as modes of operation, signs, procedures, dosimetry, and training supplement engineering controls.

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Controls

ALARA Principle

• As Low As Reasonably Achievable, social and economic factors taken into consideration.

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Controls

• Each worker has the primary responsibility for his or her own exposure.

• There are three basic practices for maintaining exposures to radiation ALARA– TIME – Reduce time spent near a radiation source– DISTANCE – Stay as far away as possible from the

source– SHIELDING - Place shielding between workers & the

source

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Controls

Access Control• Access restrictions have been established to

protect untrained personnel from unnecessary exposure to radiation and other hazards at CLS

• Visitors must be escorted at all times by trained personnel.

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Bulk Shielding

• Thick cement walls confine most of the radiation produced during operation of the storage ring

Controls

Storage Ring Outer Wall

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Bulk Shielding

• Beamline optical enclosures are lined with lead and steel to confine scattered radiation within the hutch

Controls

10 ID POE-1 11ID POE-1

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ControlsLocal Shielding• Local lead shielding has been added to further

reduce radiation levels in certain areas.• Lead coloured yellow indicates personnel protection • Lead coloured blue indicates equipment protection

Personnel Protection Equipment Protection

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Controls

Modes of Operation• Shut Down Mode – Shutdown of the accelerator

systems and beamlines• Maintenance Mode – Maintenance of the

accelerator and systems• Development Mode – To test alternate operation

configurations or commission new accelerator components or beamlines

• Normal Mode – Operation of accelerator to produce synchrotron radiation for scheduled use by Users

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Controls

Signs• Signage is used to identify Radiological Control Areas (RCA)

and materials that are radioactive.• Additional training is required for unescorted access to RCA

NOTE: RCA are subject to change

RCA EntranceActivated component

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ControlsAccess Control• Radiation levels inside beam housing areas are

significant when beam is on• Access to accelerator and beamline enclosures

during normal operation is prevented by the Access Control Interlock System (ACIS)

• Radiation levels outside shielding are very low during normal operations (< 5 uSv/h cumulative)

ACIS Panel for Beamline

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Emergency

• If you are in a beam housing area or a beamline enclosure and the red lights begin to flash or you hear the lockup horn, immediately:– Push nearest emergency off button and leave through

the closest exit– Report the occurrence to the control room operator-in-

charge

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Emergency

• All personnel must follow all radiological safety procedures

• However in emergencies concern about radiation exposure should not prevent you from performing first aid or rescue procedures

• In the event of serious personal illness or injury call 9-911

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Emergency Procedures

• Fire: 9-911– Pull Stations, Extinguishers, Evacuate– Gather at the main parking lot

• Proceed to RUH for Medical treatment– Accident/Incident Form and/or WCB Form– Form signed by Supervisor and HSE Manager

• Building Emergencies: – Authorized CLSI Staff (Info at the Lobby/Control

Room) or call Campus Security at 9-966-5555

• Health, Safety and Environment:– 227-3113

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Where to Get More Information• Discuss HSE training needs with immediate

supervisor

• Contact the HSE Manager for more info or specific training requirements

• CLS internal web site

• HSE bulletin boards