NORM Awareness - Radiation Safety Institute of Canada

NORM Awareness

May 27, 2021

Followed by Salem Dance Company

• Audio and video

– Will be from the presenters only

– Use computer or telephone (call in)

– Computer seems to give the best sound quality

• Use the “Chat” feature to enter comments

• Use the “Questions” feature to ask questions

• Posted on webinar page

– Video, Q&A answers, copy of the slides

• Follow up email will be sent

– Topics covered, time of attendance

• It may be possible to change your Zoom view if the controls are hiding the closed captioning.

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Webinar Functionality

Overview

• What is ionizing radiation?

• Radiation quantities and units

• Radiation health risks from NORM

• Background radiation

• NORM sources

– Terrestrial

– Cosmic

• NORM in industry

• ICRP recommendations

• Regulation in Canada

• Canadian NORM guidelines

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Matter & Energy

• Matter

– Has mass

– Takes up space

• Energy

– The ability to create change

– Mechanical energy

• Kinetic – movement

• Potential – stored

• Radiation

– Transfer of energy in a straight line

• Beams of particles

• Waves

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• Atom made up of

– Protons (+)

– Neutrons (0) and

– Electrons (-)

• Nucleus

– Protons and neutrons

– At the center

– Electrons orbit the nucleus

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Parts of the Atom

Nuclides & Isotopes

C-12

Protons6

Neutrons

6

C-16

Protons6

Neutrons10

O-16

Protons8

Neutrons8

• Nuclide

– Number of protons and neutrons

– Energy state

• Isotope

– Same number of protons

– Number of neutrons can be

different

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Stable and Unstable Isotopes

7

Stable: nuclear forces are strong

enough to hold the nucleus

together indefinitely.

Most nuclides in nature are

stable isotopes.

Stable and Unstable Isotopes

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Unstable atoms want to become stable!

Unstable atom: nuclear forces

are not strong enough to hold

the nucleus together indefinitely.

While becoming stable,

unstable atoms emit radiation.

Radioactive Decay

Uranium Decay Series

92238

4.5 Gy92

234

245.5 ky

90234

24.1 d90

230

75.38 ky

84218

3.1 min84

214

164.3 μs84

210

138 d

82214

26.8 min82

210

22.2 y82

206

Stable

83214

19.9 min83

210

5.01 d

81210

1.3 min81

206

4.2 min

Uranium

Protactinium

Thorium

Radium

Radon

Astatine

Polonium

Bismuth

Lead

Thallium

Mercury

Thorium Decay Series

Thorium

Actinium

Radium

Francium

Radon

Astatine

Polonium

Bismuth

Lead

Thallium

Actinides

Alkali Metals

Alkaline Earth Metals

Halogens

Metalloids

Noble Gases

Post Transition Metals

Transition Metals

90

232

Th1.41e+10Years

α

88

228

Ra5.7Years

β⁻89

228

Ac6.1

Hours

β⁻90

228

Th1.9Years

α

88

224

Ra3.6Days

α

86

220

Rn55

Seconds

α

84

216

Po0.14

Seconds

α

82

212

Pb10.6Hours

β⁻83

212

Bi61

Minutes

α

81

208

Tl3.1

Minutes

β⁻82

208

PbStable

β⁻84

212

Po3e-07

Seconds

α

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User:Tosaka, CC BY 3.0 User:BatesIsBack, CC BY-SA 3.0

Ionizing Radiation

• When radiation strikes

matter, it interacts with

the atoms of the matter

• Radiation with enough

energy can knock

electrons out of orbit

from the atoms it strikes.

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RadiationAtom

Electron

Ionizing Radiation

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Ion PairNeutral Atom

Electron

Ionization: the process of creating ions.

Radiation that can cause ionization

Non-Ionizing Radiation

Radiation that does not have enough energy to

ionize atoms

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Radio waves Infrared light

Visible light Microwaves

Non-Ionizing Radiation

Sources of Ionizing

Radiation

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Where does ionizing radiation come from?

Radioactive atoms Man-made devices

Alpha Beta

Neutron Gamma/X-Ray

Ionizing

Radiation

Types of Ionizing Radiation

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Activity

• Activity: The rate of radioactive decay.

– The number of radionuclide decays per unit of time.

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Activity

Curie (Ci): The historic unit for activity.

1 Ci = 3.7 × 1010 Bq

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1 Bq = 1 radioactive decay per second

The unit of activity is the

becquerel (Bq).

Activity Examples

1 mg of U-238

•10 Bq

1 mg of Am-241

•100,000,000 Bq

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Half-Life

• Time required for a radioactive

sample to lose 50% of its activity

by radioactive decay.

• Each radionuclide has its own

unique half-life, regardless of the

quantity or form.

– Solid, liquid, gas

– Element or compound

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Radiation Dose

• Energy given to the body by radiation per unit mass

• Measure in Gray (Gy)

Absorbed Dose

• Absorbed dose that also takes the type of radiation into account.

• Measure in Sieverts (Sv)

Equivalent Dose• Equivalent dose

that also looks at the sensitivity of specific tissues to radiation.

• Measure in Sieverts (Sv)

Effective Dose

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Types of Effects

• Deterministic Effects

– An effect which will certainly result from the exposure

– There is a minimum exposure (threshold) below which there is NO effect

– Above the threshold, the SEVERITY of the effect increases with increasing exposure

• Stochastic Effects

– An effect which might occur because of the exposure

– No threshold

– The RISK of the effect increases with increasing exposure

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The Risk - Some Numbers

• The risk of developing a fatal cancer as a

result of exposure to radiation is

approximately 4% per 1000 mSv.

– Consider a person who worked for 50

years and received 20 mSv per year.

– This person’s total lifetime radiation dose

is 1000 mSv.

– This person will have an extra 4% chance

of developing a fatal cancer.

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The Risk - Some Numbers

• Approximately 25% of people

develop a fatal cancer in their

life.

• So, this person’s risk of

developing a fatal cancer

becomes 29% instead of 25%.

• Other professions carry risks

too.

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Non-Occupational

Radiation Exposures

• Background radiation

– Soil/water

– Sunlight

– Cosmic rays

• Medical

– Diagnostic

– Treatment

– Dental

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0.9

0.3

0.3

0.2

Background Dose (mSv)

Inhalation

Ingestion

Cosmic Radiation

Terrestrial Radiation

Data from https://nuclearsafety.gc.ca/eng/resources/fact-sheets/natural-background-radiation.cfm

Origins of NORM

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U-238

Th-234Pa-234mU-234

Th-230

Ra-226

Rn-222

Po-218

Pb-214Bi-214Po-214

Pb-210Bi-210Po-210

Pb-206

Origins of NORM

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• Present throughout crust

– Solid, liquid, gas

• Can naturally release

• Can be released by human activity

• Human activity can concentrate

– TENORM

NORM in Industry

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• Mining & production

– Bauxite and Alumina production waste

– Hard rock metal mining (Gold, silver, titanium, zircon)

– Other metal mining and production waste (tin, copper, iron, steel, aluminum, niobium/tantalu, bismuth, etc.)

– Phosphate mining and processing

– Production of metallic thorium

– Rare earths mining waste

– Uranium mining waste

• Water treatment

– Drinking

– Waste water

NORM in Industry

• Consumer products

– Fertilizer

– Cement production and

maintenance of clinker ovens

– Cigarettes

– Building materials

• Energy production

– Oil and gas recovery

– Coal combustion

– Geothermal

• Tunneling and underground work

• Metal recycling

27

https://nuclearsafety.gc.ca/pubs_catalogue/uploads/March-2011-Info-0813-Alarm-Response-

Guildelines-Quick-Reference-Poster_e.pdf

Work Activities

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• Equipment maintenance

– Slag, scale, sludge

• Enclosed spaces

– Radon

• Airborne dust

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UNSCEAR/ICRP/IAEA

29Copyright IAEA

ICRP Publications 142 & 126

• NORM exposure controllable

– Justification

– Optimization

• Chronic low dose of concern

• Integrated and graded approach

• Reference levels

– Workers: typically less than 10 mSv

– Public: typically a few mSv

• Radon and thoron managed

according to ICRP Publication 126

first

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Canadian NORM Guidelines:

Purpose

• CNSC– Nuclear energy and some transport

• Provincial/Territorial jurisdiction– Not specifically mentioned in OH&S

• Federal Provincial Territorial Radiation Protection Committee

• Applies same radiation protection standards as for CNSC regulated activities

• Based on ICRP recommendations

• Principles and procedures– Detection

– Classification

– Handling

– Material management

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A NORM Management

Program

• Assessment

– Estimate doses

– Determine program classification

– Determine worker classifications

• Implement applicable radiation

protection program

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Canadian NORM Guidelines Section 3.3

Radiation Detection

• No senses to detect ionizing

radiation

• Must use instruments to detect

and measure it

• Assessment requires

measurement

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Radiation Detection

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Dosimeter

Survey Instrument

Courtesy of Landauer

Courtesy of Thermo Electron Corporation

Survey Instruments

• Measures the rate of radiation events

– Count rate, Counts per minute (cpm)

– Radiation dose rate (μSv/h)

– Exposure rate (mR/h)

• Usually hand-held

• Battery operated

• Multi-purpose

– Detector probes

– Measure all types of radiation

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Multi-purpose survey

instrument from Thermo

Electron Corporation

Worker Classification

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Canadian NORM Guidelines Section 2.4.2

• Occupationally Exposed Worker

(OEW)

• Incidentally Exposed Worker

• Members of the Public

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Recommended Radiation Dose Limits

37

Person PeriodEffective Dose

(mSv)

Occupationally

Exposed Workers

1-yr dosimetry period 50

5-yr dosimetry period 100

Pregnant OEW Balance of the pregnancy 4

A person who is not

an OEW (The Public

and Incidentally

Exposed Workers)

1 calendar year 1

Canadian NORM Guidelines Section 2.4.2

Dose limits exclude doses from natural background and medical exposures

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NORM Program Classifications

38• Canadian NORM Guidelines Section 3.1 and Figure 3.1

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Unrestricted Classification

Canadian NORM Guidelines Section 3.3 and Figure 3.1

NORM Management Classification

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Canadian NORM Guidelines Section 3.3 and Figure 3.1

Dose Management Classification

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Canadian NORM Guidelines Section 3.3 and Fig 3.1

Radiation Protection Management

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Canadian NORM Guidelines Section 3.3, Figure 3.1, and Appendix F.

Dosimetry

• Ionizing radiation

– Cannot detect with our senses

– Effects can occur years later

• Different types

– Type of radiation

– Location

• Internal or external

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Periodic Review

• Classification higher than

unrestricted

• Any changes to systems affecting

dose

• Monitor effectiveness

• Frequency

– Ability for conditions to change

– NORM program itself

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Canadian NORM Guidelines Section 3.3

NORM Material Management

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Information from Canadian NORM Guidelines Section 5

Transport of NORM

• Must assess activity concentration before transport

• >10x exempt material values

– Falls under Federal jurisdiction

– Packaging and Transport of Nuclear Substances Regulations

– Transportation of Dangerous Goods Regulations

– Offsite over public or private land

• <10x exempt material values but > unrestricted release

– Transport manifest

– Securely packaged

– Account for other properties

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Canadian NORM Guidelines Section 6

Disposal of NORM

• Provincially-licensed facilities

– Pembina Class I Hazardous Waste

Landfill, Alberta

– Unity salt cavern, Saskatchewan

– Melville salt cavern, Saskatchewan

– Silverberry Landfill, British Columbia

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Canadian NORM Guidelines Section 6 and https://nuclearsafety.gc.ca/eng/resources/fact-sheets/naturally-occurring-radioactive-material.cfm

What to Do?

• Occupational Health and Safety

– Representative

– Committee

• Provincial or Territorial Legislation

– Federally-regulated workplaces fall

under the Canada Labour Code

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