Radiation Protection Refresher
for Bone Densitometry
Dr. Craig Moore
Medical Physicist & Radiation Protection Adviser
Radiation Physics Service
CHH Oncology
THE PATIENT IS NOT
RADIOACTIVE AFTER THEY
HAVE HAD AN X-RAY
Medical X-ray Equipment
• Discovered X-rays on 8th
November 1895
• 1896 - X-ray Department set at
Glasgow Royal Infirmary
• Produced many remarkable
radiographs
• In 1896 medical x-ray diagnosis
was also started.
Frau Roentgen’s hand,
1895
Colles’ fracture 1896
First Dental Radiograph
• Otto Walkhoff (Dentist - Braunschweig, Germany)
• Jan.1896 (<2 weeks after Roentgen announced
discovery of X-rays)
• 25 minute exposure.
1 Feb 1896
• Walter Konig (physicist,
Germany)
• 9 min. exposure
• Elihu Thomson – He
immediately saw the
dangers of the new radiation
but was in a minority.
•Deliberately exposed a
finger for several days to
prove the point.
Edison’s assistant - hair fell out & scalp
became inflamed & ulcerated
Mihran Kassabian (1870-1910)
• Was a medical missionary
student and photographer
who became one of the
most prominent pioneering
radiologists of the time.
• By 1898 he had become
an American citizen
Mihran Kassabian (1870-1910)
• In 1898 he joined the
Hospital Corps of the regular
army, gaining much
experience in x-ray technique,
and paid the price
•In 1900 he describes the
damage to his hands.
•He attributed the damage to
holding the tube and putting
his hands in the beam to
reassure the patient.
In 1903 he urged
his colleagues to
discuss ways of
avoiding the
damage that could
be caused.
 1898, started work as
radiographer in Cologne - held
nervous patients & children with
unprotected hands
 After 6 months cancer of hand arm amputated
 1915 severe difficulties of breathing - extensive shadow on
the left side of her thorax - large wound on her whole frontand back-side
 Died on 22nd October 1916.
What is Radiation?
• Wave – an electric part, and a magnetic part
• ELECTROMAGNETIC RADIATION
•EM radiations spread like waves, over space.
HOWEVER, RADIATION IS NOT ABSORBED LIKE A WAVE, SO WE HAVE
TO DESCRIBE RADIATION AS DESCREET PARTICLES OF ENERGY
•Photon – a particle
•Absorption of
energy occurs in
well-defined chunks
of energy, known as
wave packets or
more correctly
photons.
Some Basic Physics –
The Atom
Outer Electrons (- ‘vly
charged) orbiting the
nucleus.
-
•
An inner Nucleus made
up of Protons (+’vly
charged) and Neutrons
(0 - zero charge), jointly
known as Nucleons.
-
+
-
-
Ionising Radiation
• Ionising radiations –
have the ability to
separate electrons
from atoms to
produce “ions”
+
Why is it
dangerous?

X-ray passes straight
through cell
No change to cell

X-ray causes a
chemical reaction in
cell, but no damage
done or damage
repaired by cell
No change to cell

DNA damaged in a
“fatal” way”
Cell killed

DNA damaged,
causing cell to
reproduce
uncontrollably
Cancer?
• Absorbed Dose (Jkg-1)
– Amount of energy deposited per kilogram
– Dose to an organ or tissue
– Unit is the Gray (Gy)
• DOSE TO A CERTAIN PLACE IN THE BODY
RADIATION
TISSUE
• Effective Dose (Jkg-1)
– This is the average dose to whole body
– Unit is the Sievert (Sv)
– This gives us the risk of contracting cancer from the x ray
exposure
• THIS IS THE OVERALL DOSE TO THE WHOLE
BODY
Effective dose
• Dose “averaged” over whole body
• Risk of inducing cancer is proportional to effective
dose, e.g.
– LD(50,30) = 4 Sv
– UK background = 2.3 mSv per year
– Legal dose limit for staff working with DEXA = 6 mSv a
year.
– Dose Investigation Level for DEXA workers = 1.2 mSv/yr
(or 0.1 mSv/month)
– Never go above 1 mSv/yr
– Usually record zero on dose badge
• Adult Exposure (per 1 mSv)
– Fatal cancer (all types)
– Fatal leukaemia
– Non fatal cancer
– Heritable effects
• Childhood exposure
– Fatal cancer
• Foetal exposure
– Fatal cancer to 15 years
– All cancers to 15 years
– Heritable effects
1 in 20,000
1 in 200,000
1 in 100,000
1 in 80,000
1 in 10,000
1 in 33,000
1 in 17,000
1 in 42,000
Risks from Bone Densitometry
Exposures
Prodigy Patient Risks
• Patient entrance skin dose
– AP spine 0.75mA thin = 12 μGy
– AP spine 3mA standard = 47 μGy
– AP spine 3mA thick = 105 μGy
• Effective dose = 0.01 mSv
– Risk of radiation induced cancer = 1 in 2 million (i.e.
negligible)
• REMEMBER – RISK OF GETTING CANCER IN OUR
LIFETIME IS 1 IN 3
• So – RADIATION CANCER INDUCED RISKS ARE
RELATIVELY SMALL
• NEVERTHELESS:
– All exposures must be JUSTIFIED
– Doses to patients, and staff, must be As Low As
Reasonably Practicable (ALARP principle) .
Prodigy Staff Risks
• 3 mA
– Edge of couch < 24 μSv/h
– 1m from couch < 3 μGy/h
• Patient entrance skin dose
– AP spine 0.75mA thin = 12 μGy
– AP spine 3mA standard = 47 μGy
– AP spine 3mA thick = 105 μGy
Prodigy Staff Risks
• Use dose constraint of 0.3 mSv a year
– Scatter 1m from couch < 3 μGy/h
– Scans about 1 minute each
– 2500 patients a year
– So dose < 3 μGy/h x 2500 x 1/60 = 125μGy =
0.125 mSv
• So
– Controlled area of 1m from couch OK
– No lead glass screen needed.
Pixi
• Beam on for 2.5 secs at 50kV then 80kV
• Dose at 50cm from unit < 40 μSv/h
• Dose to heel ≈ 200 μGy
Pixi Staff Risks
• Use dose constraint of 0.3 mSv a year
– Scatter 50 cm from couch < 40 μGy/h
– Scans about 2.5 seconds each
– < 30 exposures a day,
– So dose < 40 μGy/h x 30/d x 2.5/3600 x = 0.8
μGy/day < 170 μGy/year =0.17 mSv
• So
– Controlled area of 50 cm from Pixi OK
– No lead glass screen needed.
Calscan
• 0.5m controlled area
• Heel entrance dose ≈ 240 μGy
• Effective dose to patient = 0.2 μSv
Metriscan
• Scatter dose < 0.50 μGy per exam at edge of machine
• Patient Skin dose < 120 μGy
Recent dose results
• 1 milli-sievert (1 mSv)
= annual public dose limit
= patient dose from abdomen X-ray
= 1 in 20,000 risk of fatal cancer
• Risk of dying on UK road = 1 in 20,000
per year
• Risk from chest X-ray = 1 in 1,000,000
• Risk of meteorite killing 1/4 of world
population = 1 in 500,000
• Effective dose from natural background radiation
in the UK is approximately 2.2 mSv
– SO WE ALL RECEIVE 2.2 mSv EVERY YEAR FROM
NATURAL SOURCES AND WE CAN’T DO
ANYTHING ABOUT IT
• This natural radiation comes from cosmic rays,
rocks and soil, food, human body & radon.
Stochastic (Random effects)
– Probability of an effect depends upon total dose received
– Severity of effect is independent of the dose
– Assumed there is no threshold (i.e. there is no dose
below which effects do not occur)
– Examples are cancer and genetic defects
50%
%
40%
30%
20%
10%
0%
0
500
1000
1500
mSv
i.e. a bit like crossing the road - the more times you cross the more likely you are to be run over, but
probably never will.
37
Deterministic Effects (Certain)
– Effects are certain to occur if sufficient
radiation dose is received
– Severity will depend upon the dose
received
– There are threshold doses for
deterministic effects
• Skin ‘burn’ (or erythema) is 3 to 5 Gy
• Common in radiotherapy and
occasionally in interventional
procedures
– Examples are radiation sickness,
erythema, infertility, cataract.
Example of Radiation Injury in Cardiology
•40 year old male
•coronary angiography
•coronary angioplasty
•second angiography procedure due to
complications
•coronary artery by-pass graft
•all on 29 March 1990
Fig. A
6-8 weeks after
multiple coronary
angiography and
angioplasty
procedures
Fig. B
16 to 21 weeks after
procedure, with small
ulcerated area
present
Fig. C
18-21 months after
procedure, evidencing
tissue necrosis
Fig. D
Close up of lession in
Fig. C
From injury, dose
probably in excess of
20 Gy .
Fig. E
Appearance after skin
grafting procedure .
Hair loss from CT scan
• 53-year-old woman with subarachnoid hemorrhage
• 4 CT perfusion scans and two angiographies of the head performed within
first 15 days of admission
• Bandage-shaped hair loss seen 37 days after first CT and lasted lasted for
51 days
•
(Imanishi et al 2005)
45
3500
Staff doses never this big
5000
5000
3000
3000
2500
milli-sieverts
6000
4000
2000
2000
1000
500
500
0
150
Temp. male
sterility
Supression of
bone marrow
Detectable
opacities
(lens)
Transient
erythema
Female
sterility
Temp.
epilation
Perm. male
sterility
Cataracts
There are three principles of radiation protection:
•
Justification
–
All exposures to ionising radiations must be clinically justified –
benefit must outweigh detriment
•
Optimisation
–
Once exposure has been justified it must be optimised i.e.
lowest possible dose for acceptable image quality
•
Limitation
–
Radiation workers are subject dose limits by law
The real risk to staff
X-ray Tube
Primary Beam
Scattered Radiation
Patient
Staff
 Time
 Distance
 Shielding
•Double distance = 1/4 dose
•Triple distance = 1/9th dose.
In air, x-rays obey
the Inverse Square
Law.
I∞1/d2
Distance
• Operator B receives only a quarter of the
radiation received by Operator A if she is
standing twice the distance from the
source
• Operator B receives only one ninth of the
radiation received by Operator A is she is
standing 3 times the distance from the
source
Shielding
Shielding
• As
• Low
• As
• Reasonably
• Practicable
The ALARP Principle
And
remember
What’s the Point in Legislating?
•
•
•
Ionising radiation such as X-rays can cause
the following effects:
– Tissue damage such as skin burns and
loss of hair, and
– Stochastic (random) effects (per 1 mSv)
such as:
• 1 in 20,000 risk of fatal cancer
• 1 in 100,000 risk of non fatal cancer
• 1 in 77,000 risk of hereditary effects
– The mSv (milli-sievert) is a measure of
radiation dose
Staff receive radiation doses from X-rays that
scatter from the patient
Ionising radiation is invisible so you can’t see
or smell it, hence it can cause damage
without you knowing about it (at first!!!)
The Ionising Radiations
Regulations 1999 (IRR99)
•
Protection of
– Staff
– Public
from ionising radiation
(such as X-rays)
Authorisation
• The IRR99 are enforced by the Health and Safety
Executive in the UK
Structure of IRR99
• Legislation
• Approved code of
Practice & HSE
Guidance (approx
170 pages)
• Medical & Dental
Guidance Notes
(approx 230 pages)
So what’s included in IRR99
(relevant to DEXA)
• General Principles and Procedures
– Risk assessment
– Dose restriction
– Dose limitation
• Arrangements for the Management of Radiation Protection
– Radiation Protection Adviser
– Radiation Protection Supervisor
– Local Rules
• Designated Areas
– Controlled Areas
• Classification and Monitoring of Persons
– Dose badges
• Duties of Employees
– All of us have duties under these regulations
Reg 11: Staff and public dose limits
Reg 11: Dose Limits for staff &
public (mSv) per calendar year
Staff
Public
Whole body
dose
6
1
Lens of eye
45
15
Skin
150
50
Hands, legs etc
150
50
Whole body dose limit is low because
this is aimed at minimising staff cancer
risks from radiation exposure
Other dose limits are higher because
they are aimed at ensuring no member
of staff receives tissue damage, i.e. skin
burns of cataract
Possibly changing
to 15 mSv/yr in
2014
Reg 7: Prior Risk Assessment
• Must be undertaken before
work commences with ionising
radiations (X-rays)
– Identify hazards
– Decide who might be
harmed and how
– Evaluate risks and decide
whether existing
precautions are adequate
or not
– Record findings of risk
assessment
– Review and revise it
• By Law has to be done (or
approved) by a certified
Radiation Protection Adviser
DEXA Radiation Risk
Assessments
• Radiation Risk Assessments have been produced and
are constantly reviewed for staff working in DEXA
• The Trust Radiation Protection Adviser produces the risk
assessment in conjunction with the Radiation Protection
Supervisor
• Radiation dose to the body, extremities and eyes are
assessed.
• Any Personal Protective Equipment (PPE such as lead
aprons) required are advised
• Pregnant staff:
– By law the Trust Radiation Protection Adviser MUST
carry out a radiation risk assessment for unborn child
Risk Assessments
Reg 8: Restriction of Exposure
•
•
•
•
Doses must be optimised
– As Low As Reasonably
Practicable (ALARP)
Hierarchy of protection measures:
– Engineering controls such as the
design of X-ray tubes and
shielding
– Systems of work such as local
rules
– PPE such as lead aprons
– Dose constraints (when the RPA
is planning the design of X-ray
Rooms)
1 mSv to foetus during declared term
Formal Investigation levels of staff
dose
Female Staff of Child Bearing Age
• Staff working with radiation are
naturally concerned to
minimise the risk to a foetus
should they become pregnant
• IRR99 places the onus on the
employer to provide adequate
information and on the
employee to inform that they
are pregnant
• The employer must:
– ensure that the dose to the
foetus does not exceed 1 mSv
– Notify female employees
working with X rays the risk to
the foetus from X rays, and
the importance of informing
the employer in writing as
soon as they are pregnant
Doses and Risk to the Foetus
• Current legal limit to foetus is 1 mSv
• This corresponds to around 2 mSv to the
abdomen
• Assuming 8 months of declared pregnancy, dose
to abdomen must be kept below 0.25 mSv per
month
• Over many years, experience tells us that these
dose levels probably won’t be reached by staff in
DEXA, assuming Local Rules are followed
• Individual risk assessment must be carried
out
Reg 9: Personal Protective
Equipment
• Should be provided
where necessary, i.e.
if the risk
assessments
recommends the use
of PPE
• Should comply with
PPE regulations 1992
• Should be properly
maintained
Lead Apron Storage
• Always return to hanger
• Do not
– fold
– dump on floor and run trolleys over
the top of them!!!
• Radiology will check them annually to
make sure there are no hidden cracks
• But if visibly damaged, ask Radiology to
check them.
• IT IS VERY IMPORTANT THAT
APRONS ARE WORN CORRECTLY
AND RETURNED TO THEIR HANGER
– YOU ARE AT RISK OF
PROSECUTION BY THE HSE FOR
NOT MAINTAINING PPE
Dose Monitoring
•
•
•
•
•
Most employees who work with
radiation in a Hospital Trust have
radiation monitoring badges.
These monitor the exposure to
radiation of an employee
Doses received are assessed by the
RPA to ensure they are being kept As
Low As Reasonably Practicable
(ALARP)
If you are issued with a badge,
please ensure you
– wear it under your lead apron
during all procedures with Xrays
– Return it promptly at the end of
the month
A consultant radiologist was recently
prosecuted under the IRR99
regulations for not wearing his dose
badge (not at this Trust)
Dose monitoring results for DEXA
• Whole body
– typically less than 0.1
mSv/month (usually
records a ‘zero’)
– This equates to less than 1
mSv/yr
– Much lower than legal limit
of 6 mSv/yr
– Under reg 8 we have to set
local dose investigation
level:
– 0.10mSv/month for DEXA –
see local rules
Exemptions to Dose Limits
• Comforter and Carer
– These knowingly and willingly incur an
exposure having been fully advised of the
risks
– Not as part of their job
– Usually a family member or friend
• What about the other?
• Persons undergoing medical exposure, i.e.
the patient
Reg 12: Contingency plans
•
•
Contingency plan required for
‘reasonably foreseeable’ accident
Radiotherapy:
–
•
In Brachytherapy if the source fails to
retract during treatment:
–
–
•
•
Emergency stop buttons
Nuclear Medicine:
–
•
Take out applicators and place in lead
pot
Wire cutters may be needed in some
instances!
Radiology (inc DEXA):
–
•
Emergency stop buttons
Spills and contamination
Plan must be documented in Local
Rules
Must be rehearsed at appropriate
intervals dependent on:
–
–
–
–
–
Potential severity
Likely doses
Complexity of plan
Number of people involved
Involvement of emergency services
Part 3
Arrangements for the
Management of
Radiation Protection
Reg 13: Radiation Protection
Adviser
•
RPA must be suitably qualified
–
•
Employer must consult RPA on the following matters:
–
–
–
–
•
Implementation of Controlled and Supervised Areas (eg signage)
Prior examination of plans for installations and the acceptance into service of new or
modified sources of radiation in relation to safety and warning features
Regular calibration of equipment provided for monitoring levels of ionising radiation
Regular checking of systems of work provided to restrict exposure to ionising radiation
In addition, employer should consult RPA on:
–
–
–
–
–
•
Must be certified by HSE approved body
Risk assessment
Designation of controlled areas
Conduct of investigations
Drawing up of contingency plans
QA programmes
For HEY:
–
–
Dr. Craig Moore
Mr. John Saunderson
Reg 14: Information, Instruction
and Training
• Employees must receive
adequate training
– Risks from ionising
radiations
– Precautions to reduce
risk
– Importance of
complying with regs
• Also need training under
the IRMER regulations
(mush more physics)!!!!!
Part 5
Designated
Areas
Reg 16: Designation of Controlled
and Supervised Areas
• Based on risk assessment
• Controlled
– ……..if it is necessary to follow special
procedures to restrict significant exposure to
ionising radiation in that area or prevent or
limit the probability and magnitude of radiation
accidents of their effects,
– or any person working in that area likely to
receive effective dose greater than 6 mSv or
3/10 of any other dose limit (eye, hands etc)
Reg 16: Controlled Areas – DEXA
• Prodigy:
– 1m from couch
• Cacscan/Pixi/Metriscan
– 50cm from unit
1m
50cm
50cm
1m
Local Rules
• Local Rules must be written and adhered to for
every radiation controlled area
• Essential contents of local rules include:
– Dose investigation level
– Contingency arrangements
– Name of radiation protection supervisor &
Adviser
– Identification of area covered
– Working instructions
• You MUST work in accordance to these local
rules
Reg 17: Local Rules
•
Local rules must be provided for controlled areas
Reg 17: Radiation Protection
Supervisor (RPS)
• Local staff member to
ensure local rules are being
followed
• Must have a knowledge of
regulations and Local Rules
• Ability to command respect
• Understanding of
precautions required and
extent to which these will
restrict exposures
• Ann Goodby for DEXA
RPS must be adequately
trained
Reg 18: Additional requirements for
designated areas
• Must have physical
demarcation of
controlled areas
• Warning signs
(controlled and
supervised)
• Entry restricted to
controlled areas
Reg 19: Monitoring of Designated
Areas
• Legal requirement to
monitor dose rates around
controlled area at
commissioning
• We also have to monitoring
at appropriate frequencies
– We usually do this by
sticking dose badges up
around X-rays rooms from
time to time
• Monitoring recorded and
reviewed
• Results kept for two years
by qualified person
• Monitoring equipment
maintained and tested at
regular intervals
Reg 31:Duties of Manufacturers
• Manufacturers MUST design &
construct X-ray units to restrict
exposure & ALARP
• The manufacturer MUST
provide proper instructions on
proper use, testing and
maintenance of X-ray
equipment
• Installer of X-ray equipment
MUST perform critical
examination upon installation
• Safety features
• RPA MUST be consulted on
results of crit ex
Reg 32: Quality Assurance
Programme
•
A suitable quality assurance
programme to be provided
ensuring that equipment remains
capable of restricting exposure to
radiation
– Adequate testing before clinical
use
– Adequate testing of the
performance throughout lifetime of
equipment
– Assessment of representative
doses
•
•
Users test the performance on a
frequent basis
Medical Physicists test the safety
features, radiation dose and
image quality aspects of all X-ray
systems annually.
Reg 34: Duties of Employees
• Must not recklessly
interfere with sources
• Must not expose
themselves
unnecessarily
• Report immediately to
the RPS/Employer if
an incident or
accident has occurred
Duties of Employees – DO NOTS
•
•
•
•
•
•
•
•
•
•
•
•
DO NOT X-ray yourself (even if you think you have
broken a bone)
DO NOT X-ray your colleagues (even if you suspect
they have broken a bone)
DO NOT X-ray someone to carry out tests on the
equipment
DO NOT fail to use lead glass screen properly
DO NOT fail to wear lead aprons and thyroid collars
(if you have a thyroid collar!!)
DO NOT fail to report to your RPS any defects in
lead aprons
DO NOT fail to return lead aprons to their hangers
DO NOT tamper with dose badges
DO NOT hand badges in late
DO NOT fail to wear badges UNDER your lead
apron
DO NOT fail to inform your RPS if you believe
yourself or someone else has received an
overexposure
THE HSE HAVE PROSECUTED INDIVIDUALS IN
THE UK FOR NOT COMPLYING WITH THIS
REGULATION
Notification of Incidents
• Must report to external body when the
dose to a patient is ‘much greater than
intended’
– If it was a machine fault this must be reported
to the HSE
– If any other fault (e.g. radiographer) then
inform Care Quality Commission
Compliance with the
Regulations
• HSE Inspectorate
• Regional specialist
inspectors
• Powers of
enforcement
– Improvement notice
– Prohibition notice
– Prosecution
• Unlimited fine
• Maximum 2 years in
prison
Ionising Radiation
(Medical Exposure)
Regulations 2000 IRMER
Principles of Radiation Protection
• JUSTIFICATION
– Benefit of the radiation exposure must outweigh
risk
• OPTIMISATION
– As Low As Reasonably Practicable (ALARP)
• LIMITATION
What is IRMER?
•
•
•
•
The Ionising Radiation (Medical Exposure) Regulations 2000
The regulations apply to the following medical exposures:
– The exposure of patients as part of their medical diagnosis or treatment
including any exposure of an asymptomatic individual
– The exposure of individuals as part of occupational health surveillance
– The exposure of individuals as part of health screening
programmes
– The exposure of patients or other persons voluntarily participating in
medical or biomedical, diagnostic or therapeutic, research programmes
– The exposure of individuals as part of medico-legal procedures
‘Medical exposure’ means an exposure to ionising radiation, such as:
– Diagnostic X-rays, CT and DEXA
– Radiotherapy (including brachytherapy and therapy using unsealed
radioactive sources
– Radionuclide imaging (including diagnostic imaging and in vitro
measurements in Nuclear Medicine Dept)
MRI, lasers and Ultrasound are not covered by IRMER
IRMER
• IRMER specifically places duties on those
professionals responsible for the patient
exposure to ionising radiation
Main Duty Holders under IRMER
•
•
•
•
•
Employer
Referrer
IRMER Practitioner
Operator
Medical Physics Expert (MPE)
IRMER Referrer
• Registered Healthcare
professional who is entitled in
accordance with the with the
employer’s procedures to refer
individuals for medical
exposure to an IRMER
Practitioner
• Must have access to referral
criteria
• Must supply the IRMER
practitioner with sufficient
medical data to help him justify
exposure. Reg 5(5)
• In HEY, those who are allowed
to act as referrers are depends
on department – written
procedure must be in place
IRMER Practitioner
• Registered healthcare professional who is entitled in
accordance with the employer’s procedures to take
responsibility for an individual medical exposure
–
–
–
–
Must justify exposure
Must authorise exposure (or delegate)
Must be adequately trained – IRMER reg 11
May delegate practical aspects (operator)
In HEY dependent on
department and modality
– must be a written
procedure
IRMER Practitioner
MAIN ROLE IS TO JUSTIFY THE
MEDICAL EXPOSURE
BENEFITS OF THE EXPOSURE
vs RISKS
IRMER Operator
•
•
•
•
•
•
Any person who is entitled, in
accordance with employer’s
procedures, to carry out practical
aspects of the exposure
Functions and responsibilities of
individual operators must be
clearly defined in employer’s
procedures
Need to be adequately trained –
IRMER reg 11
No overarching responsibility
allowed
MUST optimise every exposure
Examples:
– Radiographers
– Technicians
– Physicists
Medical Physics Expert (MPE)
•
•
•
An MPE must be involved in every medical
exposure to which the IRMER regulations apply
and shall be:
– Closely involved in every radiotherapeutic
practice other than standardised nuclear
medicine practices
– Available in standardised therapeutic nuclear
medicine practices and in diagnostic nuclear
medicine practices
– Involved as appropriate for consultation on
optimisation, including patient dosimetry and
quality assurance, and to give advice on
matters relating to radiation protection
concerning medical exposure, as required, in
all other radiological practices
In this Trust, MPEs are:
X-ray
– Craig Moore
– John Saunderson
Duties of employer
• 4(1) Written procedures MUST
be in place and adhered to by
all IRMER Practitioners and
Operators
• 4(2) Written exposure
protocols MUST be in place to
ensure consistent patient
exposure
• 4(3) The employer MUST
establish
– Referral criteria (these
must be made available to
the referrer)
– QA programmes
– Diagnostic reference levels
– Upper levels of dose for
research exposures and
make sure these are
adhered to
Duties of employer
• Reg 4(4)
– Employer shall ensure every practitioner and operator
undertakes continual education and training
• Reg 4(5)
– Exposure to ‘much greater than intended’ must be
reported
• Reg 4(6)
– Take corrective action whenever patient Diagnostic
Reference Levels are consistently exceeded
– These are upper levels of patient dose that should not
normally be exceeded
Duties of IRMER Practitioner and
IRMER Operator: Optimisation
• Practitioner and operator to keep doses ALARP
• Legally obliged to make sure this happens
• Possibly the most important aspect of these
regulations
• In DEXA:
– Techs DO NOT justify the exposure
– Techs authorise under justification protocols (written
by Consultant – Dr Aye)
– Consultant justifies ALL exposures ‘by proxy’ for
DEXA
– Justification AND Authorisation are required under
regulations 6(1a) and 6(1b)
Case Study 1
• An SHO sends a
patient to the X ray
dept for chest X ray
• The radiographer
checks the request
form against
justification guidelines
written by a
radiologist and x rays
the patient
•
•
•
•
•
•
•
Who is the:
Referrer?
SHO
Operator?
Radiographer
Practitioner?
Radiologist who
writes the written
guidelines
Case Study 2
• A GP sends a patient for
a CT scan
• The details are checked
by a radiologist and the
patient is scanned by a
Radiographer. The
Radiologist evaluates the
images.
•
•
•
•
•
•
•
Who is the:
Referrer?
GP
Practitioner?
Radiologist
Operator?
Radiographer &
Radiologist (evaluating
an image is an operator
function)
Case Study 3
• A Cardiology Specialist
Registrar refers a patient
for angioplasty
• The Consultant
Cardiologist countersigns
the referral
• The procedure is carried
out in a Cath Lab under
the direction of a
Cardiologist Specialist
Registrar
• The Cardiology
Radiographer exposes
the patient to X-ray during
the procedure
• Who is the:
• Referrer?
• Consultant
Cardiologist
• Practitioner?
• Registrar
• Operator?
• Registrar
• Radiographer
Exposures of patients for research
purposes
• Must be approved by
ethics committee
• Each exposure must be
justified by IRMER
Practitioner
• Dose constraints must be
derived by an MPE
• Dose constraints must be
adhered to
• Patient must participate
voluntarily
• Patient must be informed
of the risks in advance
Image Evaluation
• Clinical Outcome
– There MUST be a
record of the outcome
of the procedure with
radiation
Clinical Audit
• Core component of clinical governance
• Must follow national procedures
Equipment
• Inventory of equipment MUST be in place
– Name of manufacturer
– Model number
– Serial number
– Year of manufacture
– Year of installation
• Avoid unnecessary proliferation – if you
have more x ray units than you need, you
are breaking the law!!!
Training
• Adequate training must be given
– Dependent upon activity
– Lots of physics
• Records must be kept
• Continual Professional Development and
training
IRMER Legal Requirement under
Reg 4(1) & Schedule 1
Employer’s Written
Procedures
Employer’s Procedures
• (a) Procedures to identify correctly the
individual to be exposed to ionising
radiation
• If we X-ray or treat the wrong patient we
have to report it to the CQC
Employer’s Procedures
• (b) procedures to identify individuals
entitled to act as referrer or practitioner or
operator
Employer’s Procedures
• (c) procedures to be observed in the case
of medico-legal exposures
Employer’s Procedures
• (d) procedures for making enquiries of
females of childbearing age to establish
whether the individual is or may be
pregnant
Employer’s Procedures
• (e) procedures for ensuring quality
assurance programmes are followed
Employer’s Procedures
• (f) procedures for the assessment of
patient dose
Employer’s Procedures
• (g) procedures for use of diagnostic reference
levels established by the employer for
radiographic examinations stating that these are
not expected to be exceeded for standard
procedures when good or normal practice
regarding diagnostic and technical performance
applied
– DRLs are doses that you shouldn’t consistently
exceed under normal operating conditions
– DAPs, DLPs, screening times
Employer’s Procedures
• (h) procedures for the use of dose
constraints for research programmes
where no direct medical benefit for the
individual is expected from the exposure
• (i) procedures for giving information and
written instructions to radioactive patients
Employer’s Procedures
• (j) procedures for carrying out and
recording of an evaluation for each
medical exposure including where
appropriate, factors relevant to patient
dose
Employer’s Procedures
• (k) procedures to ensure that the
probability and magnitude of accidental or
unintended dose to patients is reduced as
far as reasonably practicable
Enforcing Authority
• Care Quality
Commission (CQC)
• Powers of
enforcement
– Improvement notice
– Prohibition notice
– Prosecution
• Unlimited fine
• Maximum 2 years in
prison
Summary
• You must ensure you are following local
rules and procedures
• If you are not it is likely you are not
complying with IRR99 or IRMER
• You may be personally liable!!!
• Ann Goodby is the custodian of all your
radiation protection documentation
Contacts
• Radiation Protection Advisers:
– Mr. John Saunderson (461329)
– Dr. Craig Moore (461385)
• Radiation Protection Specialists:
– Dr. Tim Wood (461332)
– Mr. Andrew Davis (461330)
– Mr. Dave Strain (461331)
• Radiation Protection Supervisor:
– Ann Goodby
• Our website www.hullrad.org.uk
• New RP Trust Policy in the near future