how to handle radiation emergencies

1. EMERGENCY RESPONSE
& PREPAREDNESS
in a Radiation Department
13/21/2015
LIBIN SCARIA
Resident Medical Physicist
Dept. of Radiation Oncology

2. Outline
 Radiation Emergency
 Classification of Emergency
 Consequences
 Source of errors leading to emergency
 Regulations regarding emergency
 Handling of emergency
 Practise of safety
 Conclusion
23/21/2015

3. “Any unintended event
including operating errors,
equipment failures or other mishaps,
the consequences or potential
consequences of which are
not negligible from the radiological
protection or safety point of view”
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4. Nature of effect:
 Deterministic effect
 Stochastic effect
The affected ones:
 Public and Staff
 Patient
Effect appears:
 Immediate
 Delayed
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5. Consequences of Radiological
Emergencies
 Individuals may expose to radiation and different radiation
effect
 Radiation hazards – external & internal
 New threat - possibility of radiological terrorism
 Environmental effects
 Psychological effects
 Social problems
 Economical
53/21/2015

6. Sites of accidents
Reactor
Radiotherapy (Tele / Brachy)
Industrial radiography
Irradiation facilities
Radio pharmaceuticals
Transportation
Nuclear medicine
Radioactive waste
Orphan sources
X-ray
Scrap / Melting of metals
Acts of Terrorists / War63/21/2015

7. 7
Radiation in medicine
Diagnostic
Radiography
Nuclear medicine
Therapy
Radiotherapy
Tele-therapy
Brachytherapy
Nuclear medicine
3/21/2015

8. Potential for an accident in RT
 RT - Prescription to delivery - very complex process
which involves
- a number of steps
- a number of professionals
- several treatment sessions with many
variable parameters
 Technologists treat a number patients (50 - 80) per day
with patient specific parameters and personalized
axillary devices
 Due to complexity of equipment, techniques and
procedures, there is considerable scope for errors &
mistakes
83/21/2015

9. Radiation Accidents in RT : Classification
Radiation accidents in Radiotherapy
Events relating to
Equipment
Events relating to
Individual patient
Affects many
patients
Affects only that
patient
93/21/2015

10. Potential accidents in EXBT
Potential accidents due to machine
malfunction
Improper accessory mounting
Use of Linear accelerator in Physical mode
Mishandling of the machine malfunction
Source struck & hang up
Failure of interlocks
Inadequate training for serving personnel
Improper documentation of polices and procedures for
use & servicing of the machine
Inadequate routine QA procedures
Improper commissioning or acceptance testing
103/21/2015

11. Potential
accidents in EXBT
Possible errors in Treatment
Planning
– Incorrect input data of Depth dose or Tissue
maximum ratio
– Multiple correction for use of wedge filter or
compensators
– Wrong application of correction factors
– Misunderstanding of the algorithm
– Incorrect hand calculation and inadequate
training
113/21/2015

12. Possible errors in Calibration
Incorrect calibration of the Teletherapy unit
Using of wrong data
Use of wrong decay chart for output of cobalt unit
Not updating the output chart after source change
Lack of communication regarding units and depth
of calibration (e.g. dmax or 5 cm)
12
Potential accidents in EXBT
3/21/2015

13. Incident:
Error in calculation
 A 31 month old patient, being treated for a brain
tumor, was to receive two field treatment of 150 cGy
each, for a total dose of 300 cGy to reduce swelling
behind the eye
 Mistakenly treatment time was calculated for 300 cGy
dose per field. The patient was treated two days, with
300 cGy per field for a total dose of 600 cGy.
133/21/2015

14. Incorrect Dose calibration
 Incident:
• Wrong value for pressure was used during output
calibration of a cobalt unit in a hill station (1000m
above sea level)
 Consequence:
Patients were overdosed up to 21%
 Cause:
No barometer was available to measure pressure
Value of pressure was obtained form airport which
was corrected for sea level
143/21/2015

15. Nuclear Medicine
 Wrong patient/quantity/route of
administration/radio-pharmaceutical/activity
 Communication problems between various staff of
Nuclear Medicine department
 No proper labelling of radiopharmaceuticals
 Lack of planning and identification of patients
 No efficient quality assurance of dose calibrator
 Administration to unsuspecting female pregnant
patient
153/21/2015

16. • Spillage
• Unfamiliar with written procedures
• Busy environment, distraction
• Loss of sources
• Death of patient, with sources in situ
• Incidents in transport of sources
• Improper management of radio active
waste 163/21/2015

17. 17
A technologist scanned the
nuclear medicine request
form for a patient & noted
that it involved Tc99m-
DTPA.
He/She draw a standard
activity of the
radiopharmaceutical and
injected it before noting
that the requested study
required inhalation of the
radiopharmaceutical in
aerosol form.
3/21/2015

18. Accidents in Brachy Therapy
 Improper calibration of the source activity
 Source struck in patient/machine
 Improper identification of source
 Inadequate routine QA for source integrity
check
 Inadequate routine QA procedure for Remote
after loading unit
 Incorrect use of treatment planning system
 Insufficient understanding of TPS Algorithm
183/21/2015

19. Potential accidents in BT
 Inadequate source movement documentation
 Improper and inadequate training of personal
on radiation protection aspects
 Insufficient documentation of policies and
procedures for handling emergencies
 Use of faulty zone monitors and survey meters
 Loss of source
 Manuel handling of source
193/21/2015

20. Error in activity reporting
• Incident:
Error in units of reporting the activity for brachytherapy
ribbons
• Sequence:
– the licensee ordered brachytherapy ribbons containing
0.79 mCi per ribbon
– however, the vendor delivered ribbons containing 0.79 mg
radium equivalent (1.36 mCi) per ribbon
– the received shipment was checked against the order and
noted that the quantities (0.79) matched
– but failed to note that the amount received was measured
in mg radium equivalent rather than mCi
203/21/2015

21. Diagnostic Radiology
• Fluoroscopy in interventional
procedures
• Applications in Cardiology,
General Radiology & Neuro-
Radiology
• More extended periods of time
• Multiple use of Radiography
• High exposure for both patients
and personnel
 No proper regulations
in diagnostic radiology
213/21/2015

22. 22
Cataract in the eye of
interventionalist after repeated
use of old x ray systems and
improper working conditions
related to high levels of scattered
radiation.
Examples of injury when female breast is exposed to direct beam
3/21/2015

23. 3/21/2015 23

24. 24
One should never
attempt to tackle the
problem hurry without
analysing the situation,
because such an
attempt will not only
complicate the situation
but also will result in
unnecessary radiation
exposures
3/21/2015

25. 3/21/2015 25
Rule – 33 of Atomic Energy
(Radiation Protection) Rules, 2004
 The licensee shall prepare emergency
response plans and submit the plan to
the Competent Authority for review
 Any modification to the emergency
response plan shall require prior
approval of the Competent Authority
 Special directives in case of accidents
are issued by the Competent Authority

26. Responsibilities of Licensees
 In consultation with Radiological Safety Officer, prepare
emergency plans
 Take protective actions required for the protection of workers &
the public, if an emergency occurs
 Inform the employer, the competent authority , law enforcement
agency of any loss of source
 In consultation with the RSO, investigate any case of over
exposure & maintain records of such investigations
 Inform competent authority promptly of the occurrence,
investigation and follow-up actions in cases of exposure
 Carry out physical verification of radioactive material periodically
and maintain inventory
263/21/2015

27. Responsibilities of RSO
 Developing suitable emergency response plans to
deal with accidents and maintaining emergency
preparedness
 Investigate any situation that could lead to
potential exposures
 Carry out routine measurements and analysis on
radiation and radioactivity maintain records
 Initiation of suitable remedial measures in
respect of any situation that could lead to
potential exposures
 Safe storage and movement of radioactive
material within the radiation installation
 Reports on all hazardous situations along with
remedial actions taken are made available to the
employer & licensee
273/21/2015

28. 3/21/2015 28
Elements of Emergency
Preparedness
 Emergency management within the Institution
(Emergency Response Committee)
 Emergency Response Manual
- Action plans for each type of Emergency
- Emergency contact details
 Communication System
 Training
 Emergency drills & exercise

29. Steps to follow
 Evacuate the immediate area & regulate entry
 Identify, segregate and treat all exposed individuals
 Assess the extent of exposure
 Carry out decontamination in case of
decontamination
 Samples from contaminated area should be analysed
urgently to take further action
 Use of periodically calibrated radiation measuring
devices
 Instruments to collect & handles
samples in case of contamination
293/21/2015

30. Management of Emergency
 Emergency reporting: RSO, licensee ,AERB & law
enforcement agency
 Priority should be given to human safety &
personnel dose should be restricted within limits
 Arrange for immediate availability of experts who
are trained to deal with emergency
 Maintain complete records of accident and
follow up procedures
 If accident is in public area it should be cordoned
off and appropriate authorities will be contacted
for further action
303/21/2015

31. 31
T-Rod
3/21/2015

32. Source struck in TeleCobalt
 Try to stop the irradiation
using emergency key/button
 Close collimators to a minimal
field
 Rotate gantry/table so patient
is removed from the primary
beam
 Remove patient safely and
quickly from the room
 Route to enter the room
should be chosen logically
 Audio instructions can be
utilized effectively
 One person may remain
outside & make a note of the
time taken for the sequence of
steps
 Division of labour
 Persons entering room should
carry personnel dosimeter
 If the source does not return it
might be necessary to push it
back to a safe position using an
emergency rod
 The RSO should be contacted,
the room door closed and a
warning sign hung on the door323/21/2015

33. Accident spills
33
• RSO & individuals
in immediate
work
inform
• Prevent further
contamination
contain
• Decontaminate:
personnel &
work area
Decontaminate
3/21/2015

34. Steps in Decontamination
• Individuals nearby, RSO should be
informed & entry should be
banned
• Prevent further contamination
with out risking ourselves
• Absorbent pads should be thrown
over a liquid spill
• Doors should be closed to prevent
the escape of airborne
radioactivity
• Personnel monitoring should be
started as soon as possible
• Separate contaminated and
uncontaminated
• Use sensitive radiation
monitoring instrument
• Contaminated protective
dressing must be removed &
kept in plastic bag
• Skin can be flushed with water
• Open wounds, eyes , nose and
mouth requires special care
• Floor should be decontaminated
• Clean ‘from outside in‘ to reduce
spread
• If complete decontamination is
not possible better is to shield &
cover the affected areas
343/21/2015

35. Source stuck in Brachytherapy
• Press the button on control
console or door display panel
• If it is not possible, enter
treatment room with a
portable survey meter &
personal dosimeter press stop
button on after loader unit
• If source still remain outside,
use hand crank
• If there is no indication that
source is still in patient remove
him/her from the treatment
room
• if it shows presence of
radiation remove the
applicator and keep in
lead container
• Check the radiation
levels
• If it shows no radiation,
remove the patient from
treatment room
• Use forceps in removing
the applicators
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36. 3/21/2015 36
Medical management of
Emergency
Clinical care
Biological evaluation
Identification of emergencies

37. Samut Prakan radiation accident
Gammatron -3 Teletherapy unit
Date : 24 Jan 2000 to 21 Feb 2000
Location : Bangkok, Thailand
10 people affected, 3 died
Office of Atomic Energy for Peace (OAEP) solved the problem
373/21/2015

38. Mayapuri radiological accident
AECL Gammacell 220 researchirradiator owned by Delhi University
Date : April 2010
Location : Mayapuri, Delhi, India
8 people affected. One died
DAE solved the issue.
383/21/2015

39. 393/21/2015

40. System of Radiological Protection
• Justification of Practice:
No practice involving exposures to radiation should be
adopted unless it gives benefit to the exposed individuals
• Optimization of Protection (ALARA) :
In any practice, the magnitude of individual doses, no. of
people exposed, and likelihood of incurring exposures,
should all kept as low as reasonably achievable
Time - - Distance - - Shielding
• Individual Dose & Risk limits :
Exposure of individuals should be subject to dose limits or to
some control of risk in the case of potential exposures. These are
aimed at ensuring that no individual is exposed to radiation risks
that are judged to be unacceptable
403/21/2015

41. References
• Chapter 11,Textbook of Radiological Safety, K
Thayalan, Jaypee publishers
• Presentation on Radiation Emergency, Dr. Hemant
Haldavnekar, Scientific Officer ‘G’,BARC, Mumbai
• Presentation on Radiation Hazard Evaluation,
Naushad N, Scientific officer, AERB
• www.iaea.org
• www.aerb.gov.in
• www.google.co.in/images
3/21/2015 41

42. Conclusion
• Rethinking regarding safe practise of
radiation
• Chances for multiple number of errors
to occur
• Handling of emergencies
• Responsibilities of different radiation
professionals
• Examples of errors happened
 Learning from past
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43. 3/21/2015 43
The safety and
happiness of
society are the
objects at which
all institutions
aim, and to which
all such
institutions must
be sacrificed
James Madison
Fourth President of
United States

44. thank you..
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