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Radiation and Radiation Safety at the
Australian Synchrotron (GERT Training)
Sergio Costantin
Radiation Safety Officer
Australian Synchrotron
Training Objectives (questions that will be answered)
• What is radiation and where does it come from?
• What are the different types of radiation present at the
synchrotron?
• What effect does exposure to radiation have on me?
• How is radiation monitored at the facility?
• How will people be stopped from going into radiation areas?
• How will people be warned about radiation and radiation areas?
• How do I minimise my radiation dose?
• To how much radiation will I be exposed and what is the risk?
What is Radiation?
The different types of particle
radiations are:
• alpha radiation
(alpha particles);
• beta radiation
(beta particles); and
• neutron radiation
(neutron particles).
Particulate Radiation
Radiation is the process of emitting
energy as waves or particles.
Diagram indicates the penetrating power of
the different types of radiations.
What is radiation and where does it come from?
Wave Radiations – Electromagnetic Spectrum
Radiation can be the
process of emitting
energy as waves.
The full
range of wave energies is
called the
electromagnetic
spectrum.
What is radiation and where does it come from?
Types of Radiation
Ionising radiations are capable
of producing ionisation as they
pass through matter, i.e. radiation
energetic enough to strip atoms
of electrons.
Ionising Radiation
Non-ionising Radiation
What is radiation and where does it come from?
Units for Measuring Ionising Radiation
Radiation Dose
• When something absorbs radiation, the energy of the
radiation is deposited (or absorbed) in that material.
• The amount of energy deposited in the material by an
exposure to ionising radiation is often referred to as a
radiation dose and can be expressed in joules per
kilogram (J/kg).
• The weighted radiation dose (taking into account the
type of radiation and the area of the body exposed)
is given the unit of sievert (Sv).
• One sievert (1 Sv) of radiation is a very large radiation dose.
Most often radiation doses are expressed as fractions of
sieverts, for example in micro (µSv) or milli (mSv).
[Swedish physicist
Rolf Sievert (1896-
1966), first professor
of the Dept. of
Medical Radiation
Physics in
Stockholm, did a lot
of work in radiation
protection.]
What is radiation and where does it come from?
Radiation is everywhere, it is a natural part of our environment.
This radiation is often called Background Radiation.
Background radiation may be either from natural sources or
human-made sources.
What is radiation and where does it come from?
Background Radiation Exposure to natural sources comes from: Cosmic rays,
ionising radiation
from the Sun and
outer space.
Naturally occurring
radioactive
materials found in
the earth such as
uranium, radium
and thorium.
Radon, a naturally
occurring
radioactive gas,
that comes from
radium present in
the soil.
Ingestion of naturally
occurring radioactive
elements in food,
such as potassium-40
(K-40), and water.
What is radiation and where does it come from?
Background Radiation
Exposure to human-made sources comes from:
Medical X-rays and nuclear
medicine (i.e. medical procedures).
Consumer products such as
smoke detectors and lantern
mantles.
Fallout from nuclear weapons
testing present in the
environment.
Nuclear reactors for power
generation.
What is radiation and where does it come from?
Background Radiation in Australia
Background Radiation
(Melbourne avg):
~2.2 mSv per year
(or 2,200 µSv/year)
(less than the World avg of 2.4 mSv).
Australian annual per capita
radiation dose (in mSv) from
natural and medical sources. (Source ARPANSA)
Medical Diagnostic
(35%)
0.8
Radon Progeny
(9%)
0.2
Potassium-40 in
the body (9%)
0.2
Terrestrial (26%)
0.6
Uranium/Thorium
in the body (8%)
0.2Cosmic Rays
(13%)
0.3
mSv
mSv mSv
mSv
mSv
mSv
What is radiation and where does it come from?
There are three sources of ionising radiation present at the
Australian Synchrotron (when it is operating).
Bremsstrahlung radiation
(equivalent to gamma/X-ray radiation)
Neutron radiation
Synchrotron radiation (from ultra-violet to X-ray radiation)
Radiations Present at the Synchrotron
There is also non-ionising radiation present at the Australian
Synchrotron (when it is operating).
Radiofrequency radiation } present at most
Microwave radiation } accelerator facilities
Synchrotron radiation (from infra-red to ultra-violet)
What are the different types of radiation present at the Synchrotron?
non-ionising hazard
ionising hazard
Synchrotron Radiation (from Infrared radiation to X-ray radiation)
• Radiation emitted when electrons, travelling at close to the
speed of light, are forced to move in a circular orbit under the
action of a magnetic field.
What are the different types of radiation present at the Synchrotron?
• The synchrotron radiation
is emitted in a narrow cone
in the forward direction, at
a tangent to the orbit.
Radiations Present at the Synchrotron
Important to Remember
• Ionising radiations, as a result of the electron beam, are
present only when the beam is operating or being
accelerated.
• No different to turning off a light
– there is no ‘residual light’ left
in the darkened room.
Radiations Present at the Synchrotron
• NOTE: Non-ionising radiations
are normally present when
power is provided to equipment.
What are the different types of radiation present at the Synchrotron?
• Materials in close contact to the
electron beam (i.e. inside the tunnels)
may become activated, that is,
become radioactive.
• If you are working close to activated
material you may be exposed to
radiation levels slightly higher than
background.
• Activated components will be
labelled.
What are the different types of radiation present at the Synchrotron?
Radiations Present at the Synchrotron
What effect does exposure to radiation have on me?
Non-ionising radiations
Under normal conditions
there are no effects.
When exposed to high
radiation levels the main
effect of non-ionising
radiation is to heat the
body.
The body has many defence
mechanisms to dissipate heat.
What effect does exposure to radiation have on me?
Ionising radiations:
Under normal conditions
there are no effects.
Exposure to high levels of
ionising radiation gives
rise to an increased risk
of cancer.
At the Australian Synchrotron
any increased risk is small and
comparable to other everyday
risks.
Radiation Monitoring Equipment.
Radiation levels around the facility are
monitored using radiation detection equipment.
Radiation Monitoring (Ionising Radiation)
How is radiation monitored at the facility?
gamma radiation
monitors
neutron
radiation
Monitor
Monitoring Equipment
(non-ionising)
• Narda EMR-300 with type 8C
E-Field probe (100 kHz to 3 GHz)
Radiation Monitoring (Non-ionising radiation)
How is radiation monitored at the facility?
Personal Monitoring (TLD/neutron & Luxel badges)
The Australian Synchrotron has been given
an exemption from personal monitoring for
Users by its radiation Regulator (ARPANSA).
This exemption was given based on seven
years of data showing that the facility has
maintained radiation doses to personnel at
less than 1 milliSv/year.
A personal radiation monitor WILL NOT
normally be provided to you unless a specific
request is made.
This request must be made at least one
week prior to your allocated beam time.
How is radiation monitored at the facility?
Personal Monitoring (TLD/neutron & Luxel badges)
Personal monitors will continue to be used by
Staff, other specific personnel and under
some special circumstances.
The special circumstances are:
o Where explicitly required by the Safety
Office.
o Where a person declares pregnancy.
The Safety Team is to be consulted regarding
availability and accessing a personal radiation
monitor.
How is radiation monitored at the facility?
Personal Monitoring (TLD/neutron & Luxel badges)
IF YOU ARE PROVIDED WITH A
PERSONAL RADIATION MONITOR
THE FOLLOWING APPLY:
How is radiation monitored at the facility?
Worn by individuals to assess their personal radiation dose.
Provided by (independent) external service providers.
Preferred wearing location: upper torso.
NOTE: DO NOT HANG BADGE ON YOUR LANYARD.
Approximate ten week wearing period (hence same badge
available for approximately ten weeks).
Note: No instantaneous reading; must be sent away to the
service provider to determine radiation doses.
Users’ badges are placed in the foyer.
Radiation dose results are available from the Radiation Safety Officer upon request.
Must be worn at all times while at the synchrotron facility.
Lost or damaged badges must be reported to the Radiation
Safety Officer / Safety Office immediately.
Must not leave the Synchrotron facility.
Must not be left in a Radiation Area.
Must not be intentionally tampered or interfered with.
Must not be worn during non-occupational activities, such
as when undergoing medical or dental X-rays, nuclear
medicine procedures or during air travel.
Personal Monitoring (TLD/neutron & Luxel badges)
How is radiation monitored at the facility?
IF YOU ARE PROVIDED WITH A PERSONAL MONITOR
THE FOLLOWING REQUIREMENTS APPLY:
MUST
MUST NOT
Pocket dosimeters can be used to give an
instantaneous reading of radiation dose
levels to individuals.
May be required (as part of a procedure)
to wear a pocket dosimeter while working
in a particular area.
Available from Control Room.
Must complete log book when taken:
Date, Name;
Serial number of dosimeter;
Time Out, Dose Out;
Dose In, Time In.
Radiation Monitoring (Ionising Radiation)
How is radiation monitored at the facility?
How will people be stopped from going into radiation areas?
The facility has a Machine Personnel Safety
System and Beamline Personnel Safety
System to stop entry into radiation areas.
Personnel Safety System (PSS)
The function of the PSS is to prevent
personnel from being harmed from
exposure to ionising radiation
generated by the electron beam.
Machine Access Modes
Open access: Allows unlimited, open access
to authorised personnel.
Authorised access: Limited, controlled
access to a specific zone for a specific
purpose. Radiation hazards interlocked off.
Electrical hazards may be present. SOP must
be followed
The design of the PSS allows three access modes into
the tunnel areas:
How will people be stopped from going into radiation areas?
No access: Radiation and electrical hazards present; no personnel
allowed. Blue lighting in tunnels indicates no access mode.
NOTE: Entry into the tunnels is to authorised personnel ONLY.
Beamline Access Modes
Open access: Allows unlimited, open access to authorised
personnel. (green light)
The design of the PSS allows three access modes
into the beamline enclosures:
How will people be stopped from going into radiation areas?
Search and secure mode: enclosure has
been searched and secured and is ready
for beam. (orange light)
No access: Radiation hazard present; no
personnel allowed. (red light)
Radiation Warning Signs
Radiation areas display
radiation warning signs.
How will people be warned about radiation and radiation areas?
How will people be warned about radiation and radiation areas?
Area Radiation Monitoring
TLDs and small radiation
dosimeters are placed at
various locations throughout
the facility to assess radiation
doses at specific locations.
How will people be warned about radiation and radiation areas?
Red Lights (normally) indicate that radiation is present,
e.g. inside the accelerator tunnels
or inside a beamline enclosure.
Warning Lights
How will people be warned about radiation and radiation areas?
During the injection process of the
electron beam (electron beam transferred from
Booster Ring to Storage Ring) orange lights will
flash at locations on and within the
Storage Ring. (Not to be confused with forklift warning lights which are
located under the mezzanine level.)
During this period radiation levels within
the facility are slightly higher than
during normal operation.
(Use distance to help minimise radiation dose.)
Warning Lights
• Sign / label to indicate important
configuration items.
• Item NOT to be
modified or removed
without proper (written)
authorisation.
Other Radiation
Warning Signs / Labels
Other radiation controls within the facility.
• All shielding panels of
beamline enclosures are
painted blue (aqua).
(Note, two shades – inside
lighter than outside.)
• Any item in this colour must
not be interfered with
(modified or removed) in any
way, without (written)
authorisation.
Warning Indicator (Paint Colour of Beamline Enclosures)
Other radiation controls within the facility.
Permission must be granted to
access the facility beyond the foyer
and viewing gallery.
The Technical/Beamlines floor
area is a Controlled Area.
Only persons who have completed
safety induction training may work in
this area.
Visitors to a Controlled Area must be
escorted by a staff member at all
times.
Facility Access
Other radiation controls within the facility.
There are three basic principles to protection from radiation.
(3) TIME
Three Principles of Radiation Protection
(1) SHIELDING (2) DISTANCE
How do I minimise my radiation dose?
Placing adequate
shielding between
you and the
radiation source will
minimise the amount
of radiation you
receive.
Three Principles of
Radiation Protection - Shielding
How do I minimise my radiation dose?
Radiation Shielding
Photon radiation (gamma & X-ray radiation)
Normally requires significant thicknesses of dense
material, such as lead or tungsten.
Neutron radiation
Best shielded by materials with a lot of ‘light’
atoms, eg materials that contain hydrogen, such
as paraffin, water and concrete.
How do I minimise my radiation dose?
Maximising the
distance from a
radiation source will
minimise the amount
of radiation you
receive.
Three Principles of
Radiation Protection - Distance
How do I minimise my radiation dose?
Minimising the
time you spend
near a radiation
source will
minimise the
amount of radiation
you receive.
Three Principles of
Radiation Protection - Time
How do I minimise my radiation dose?
The radiation Regulations set the
Occupationally Exposed Persons limit at 20,000 µSv/year
and the Public Exposure limit at 1,000 µSv/year.
Regulatory Requirements – Exposure Limits
The facility has systems and controls in
place to help minimize exposure to
radiation. The dose constraint at the
facility is to keep all radiation doses to
less than 1,000 µSv/year.
Our goal, however, is to always keep all
radiation doses As Low As Reasonably
Achievable (ALARA principle).
To how much radiation may I be exposed?
• Radiation is a natural part of the environment.
• At the Australian Synchrotron you will not be exposed to
any significant levels of radiation (both ionising
and non-ionising).
• Signs and barriers are used to advise where radiation is
present and to control access to those areas.
• SHIELDING, DISTANCE & TIME will minimise the amount of
radiation you will receive.
• Our aim is to ensure that all radiation doses are as low as
reasonably achievable (ALARA principle).
• The risk from a low level of radiation exposure is no
different to other risks faced everyday.
Summary (the facts)