Transcript Radiation Protection Instruction

Norbert Tesch - D3 -
2.12.2003
10.12.2003
Radiation Protection
Instructions
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Laws and Regulations
Dose and Dose Measurement
Radiation Protection Precautions
DESY Internal Rules and Regulations
News
Laws and Regulations
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Strahlenschutzverordnung
(StrlSchV)
Regulation about construction and operation of
installations for generation
of ionizing radiation and
handling of radioactive
substances
Röntgenverordnung
(RöV)
Regulation about operation
of X-ray devices and
„Störstrahler“
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Permissions of the
inspecting authority
Operation of accelerators
and „Störstrahler“, legal
constraints
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DESY internal regulations
Radiation Protection
Instructions
(„Strahlenschutzanweisung“),
regulations about
responsibilities,
operation sequences for accelerators,
dealing with radioactive substances
Radiation Protection Organization
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„Strahlenschutzverantwortlicher“
at DESY:
Directorate
in person Herr Trines
Radiation Safety Officers
at DESY:
46 persons for
30 different areas
List of Radiation Safety Officers at DESY
To be found on D3-Homepage!
Dose Definition and Examples
Dose means measuring the risk
 Definition: Dose = in the human body (tissue)
absorbed energy per mass x biological factor
 Unit: 1 Sv (Sievert) = 1 Joule / kg
(for photos and electrons)
 Examples:
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Flight from Frankfurt to New York and back
0.1 mSv
Limit for „beruflich nicht strahlenexponierte Pers.“
1 mSv/Jahr
Natural radiation level in Germany
1-2 mSv/Jahr
Limit for category B persons
6 mSv/Jahr
CT in breast or abdomen region
5-30 mSv
Lethal dose in case of single whole body exposure
4-5 Sv
Measurement of Personal Dose
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New: From January 2004 on there
will be new personal dosimeters !!!
Distribution starts at 15.12.2003
The new dosimeter consists of a
combination of photon and
neutron dosimeter
 Photon dosimeter (PLD, photo luminescence
dosimeter, Messstelle für Strahlenschutz, HH,
Dose >= 0.1 mSv)
 Neutron dosimeter (nuclear track emulsion,
Messstelle der GSF, Dose >= 0.1 mSv)

Change of controlled area declaration
Personal dosimeter belong to one person !!!
Measurement of Personal
Dose and Local Dose
 Directly readable dosimeter
– Electronic dosimeter
– Rod dosimeter
 static fields
– Dosimeter
automess AD 2
 pulsed fields
– Ionization chamber
Babyline 31A
Statistics of Personal Dose
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Yearly monitored persons at DESY:
– Photon dosimeter: 1300 (2002)
– Neutron dosimeter: 300 (2002)
persons group
(StrlSchV)
yearly dose
in mSv
„beruflich nicht
strahlenexponiert“
2002
2003 (until 09)
Phot.
Neut.
Phot.
Neut.
0.1 – 1
27
2
62
0
category B
1–6
0
0
0
0
category A
6 – 20
0
0
0
0
> 20
0
0
0
0
Radiation Sources at DESY
Accelerators
Synchrotron radiation (Röntgen)
Beam losses (e-, p-shower)
Secondary radiation (g, neutrons)
„Störstrahler“
Radioactive Material
Radioactive sources (a, b, g)
Activated material (a, b, g)
Klystrons (Röntgen)
Cavities (Röntgen, g)
Radiation Protection Actions
Duration of Stay
Shielding
Distance
Instruction
Labelling
Interlock System
Labelling of Radiation Fields
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Radiation protection areas:
– Prohibited Area
– Controlled Area
Labelling of radioactive materials:
VORSICHT RADIOAKTIVITÄT
Measurement and labelling will be done
by the radiation protection group
Prohibited Area
Definition:
local dose > 3 mSv per hour possible
 Labelling:
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Entry to a
prohibited
area is
forbidden!!!
Exceptions are
labelled in addition
If there is any doubt always ask the BKR !!!
Where are
Prohibited Areas
at DESY?
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All accelerator areas, if
the accelerator is switched
on, the prohibited area is
then secured by an
interlock system
Some close by areas if
the accelerator is switched
on, e.g. tunnel shielding at
PETRA, HERA, Linac 3 and
TTF 2
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Areas with accelerator
sections during operation
with high HF power, the
prohibited areas is then
secured by an interlock
system
Linac 2: Area near
converter is always a
prohibited area!!! Exception
only for this prohibited
area: fast passage is
permitted
Controlled Area
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Installation at DESY:
personal dose > 1 mSv per year possible
Labelling:
New from 5.1.2004 on: No
controlled areas with addition
„N“ anymore, because of new
combined photon and neutron
dosimeter
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New: Therefore all special
regulations for „N“ areas
(e.g. special extra dosimeter
or 4 hours rule) are obsolete
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Exceptions are labelled in addition
If there is any doubt always ask the BKR !!!
Where are Controlled
Areas at DESY ?
Accelerator
switched on
switched off
Linac 2
modulator hall
modulator hall
accelerator area
Linac 3
from DESY 3 operation: parts of
control room near DESY 3
accelerator area
DESY 2/3
“Kondensatorgärten”
passage near hall 2
“Kragdecken” hall 1+2
center, radial canal, SER
test beams hall 2
old Linac 1 building
accelerator area
center (“Zentrum”)
radial canal
SER
Where are Controlled
Areas at DESY ?
Accelerator
DORIS
PETRA
TTF 2
switched on
switched off
cellars
none
building 18 annex
(“Werkstattlager”)
some parts in halls
hall SO inner part
area close to
p septum SO
area close to
p dump W
to be decided
accelerator area
New Controlled Areas !!!
Accelerator
HERA N
from 1.12.2003
HERA S
from 15.12.2003
HERA W
from 15.12.2003
HERA O
from 15.12.2003
switched on
switched off
room 100
(experimental hall),
side stairs from 6. floor on
none
room 100
(experimental hall)
area near uranium
calorimeter
complete (from entrances)
exception: rooms of BSG
tunnel WL: from fire door
to p injection (200m)
room 100
(experimental hall)
none
Staying in Controlled
Areas at DESY
 Entry
is only
allowed if
– there is a working
mission
– the personal dose will
be measured
– a radiation protection
instruction was
received
 Entry
is not
allowed for
– people under 18
years
– pregnant and
nursing women
 In
controlled areas
forbidden:
– eating, drinking
and smoking
Guests in Controlled Areas
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Guests (e.g. workers from other companies) are only
allowed to work occasionally in controlled areas and
need the following:
– working mission
– personal dosimeter
– radiation protection instruction
Their time of stay in controlled areas must be arranged such
that the personal dose can not exceed 0.5 mSv per year,
if the company has no “§15 Genehmigung nach StrlSchV” (in
the moment only the company ABB has such a permission)!
The personal doses will be regularly checked by D3!
Particular restrictions for guests are valid for the
“Kondensatorgärten” and the Linac 2! Access to
these controlled areas is not allowed for guests!
Exceptions can be arranged with D3!
Visitors in Controlled Areas
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Visitors (do not work in controlled areas) are only allowed to
enter controlled areas accompanied by a competent expert
(wearing his personal dosimeter) knowing the corresponding
place and only for a short visit
Visitors must get a short instruction before they enter the
controlled area
Visitors need a directly readable dosimeter
if they visit Linac 2, PIA, DESY 2/3 or TTF 2
The visit, the short instruction and
the measured value of the visitors dosimeter
must be documented
New: Visitors are not allowed to enter the controlled
areas of the HERA halls !!!
But visitors have free access to these areas with labelled
exception if there is “Wartungstag”
(If there is any doubt always ask the BKR !!!)
Contents of Instructions
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General instruction
– Introduction to basics
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Special work place related instruction
– Special questions and dangers of the work place
– Has to be done in responsibility of the
corresponding radiation protection officer
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Instruction of guests
(e.g. workers from other companies)
– Dangers and risks due to radioactivity
– Prohibited areas and controlled areas
– Behavior in radiation fields
– Information about possible radioactivity
– Instruction is given by triggering DESY colleague
or corresponding radiation protection officer
– Documentation of contents of instruction
and signature of instructed person
(forms on D3-Homepage)
Interlock System
Prevents in case of danger beam operation of the accelerator
 Before an accelerator is switched on:
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Search of the accelerator tunnel
Warning message
Yellow warning lamps
Lights will be dimmed
 Actions in case of
danger:
– Push an
emergency
button or
– Escape
through an
interlock door
Controlled Access (“ZZ”)
Colleague arrives at
closed interlock door
(red lamp is on)
Colleague gets in contact with
BKR via telephone and TV
Operator notes down names,
place and time
Controlled Access (“ZZ”)
Colleague takes from the
key cabinet exactly 1 key
per person !!!
Operator checks again that the
accelerator is switched off and
bridges the door contacts
Colleague opens the door only after the
red lamp (door tableau) is switched off
Working at Accelerator
Components
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Radiation field has to be measured
will be done by D3
Wear your personal dosimeter
if necessary additional active dosimeter
Keep distance from labelled locations
Wear working clothes, wash your hands
Note limitation of stay
for guests (other companies)
Demounted components have to be measured (D3)
– Accelerator areas with controlled areas: all components
– Other accelerator areas:
beam pipes, cavities
and all components
which were located
near or in the beam
pipe
Handling Radioactive Material
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Storage outside accelerator areas:
Theft protection and labelling needed
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Shipment:
Only in agreement with D3
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Wear personal dosimeter
Mechanical processing:
Only in agreement with D3
Waste disposal: Never in trash or
scrap, waste disposal only through D3
Transport on DESY site and to HERA halls
only by instructed people
Radiation Protection
and www
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Additional important information can be found on the
D3-Homepage www.desy.de/d3/d3indexe.html:
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Laws and regulations
DESY internal regulations
Radiation protection organization
Responsibilities inside D3
Radiation protection instructions
Important dates
and a lot more ...
If there is anything missing or you have any
questions: Please talk to us !!!